A friend and colleague who prefers to remain anonymous has asked me to post the following. For reasons you can probably guess, I haven’t had time to take a hard look at the numbers.
By now everyone already knows about the spat between Israeli PM Netanyahu and the Obama administration over “red lines” for the Iranian nuclear program. The New York Times explains what was behind it:
“The Israelis are worried that once Iran accumulates a bomb’s worth of 20 percent-enriched uranium, it’s an easy dash to get weapons-grade nuclear fuel,” said David Makovsky, a senior fellow at the Washington Institute for Near East Policy, who met recently with Israeli officials. “Before they decide they’re on their own, I think they want to know that they and Washington see eye-to-eye that this is a red line that cannot be passed.”
In the annals of Israeli red lines for Iran’s nuclear program, “a bomb’s worth of 20 percent-enriched uranium” is only the latest threshold criterion, but it’s by far the most specific. (Compare it to “the point of no return” and “the zone of immunity.”) So, by this measure of breakout capability, just how close is Iran, anyway?
The answer is, they’re already there!
First, let’s establish a little more clearly what’s being discussed. Former Israeli deputy national security adviser Chuck Freilich recently explained it this way in the Jerusalem Post:
The Netanyahu government, convinced that sanctions have failed and that Iran is rapidly nearing both nuclear capability and the point of invulnerability to an Israeli attack, has clearly begun preparing public opinion for a military strike. The Obama administration, preoccupied with the elections, continues to cling to sanctions, stressing that the US’s unique military capabilities will still enable it to act for some time and thus that it is too early for a strike.
Technically, this is true, but Iran is just months from having sufficient fissile materials for its first bomb and if it disperses them, or actual bombs once operational, around the country, the US too will no longer have the ability to strike.
What this seems to describe is a diversion scenario, with a stockpile of 20% enriched uranium being raced out of storage to one or more hidden sites where it would be re-enriched to weapons grade and then fashioned into a bomb. This idea appears to be born of the conviction that Iran is racing to get to its first bomb at any cost, and all other objectives and considerations are negligible. Call it the worst-case scenario.
You could also call it overtaken by events.
Bring on the numbers!
The IAEA’s latest report on Iran, GOV/2012/37, says that Iran has produced, at last measure, “189.4 kg (+43.8 kg since the previous report) of UF6 enriched up to 20% U-235.” UF6 is the gas containing uranium that’s fed through the enrichment process, and would be used in the diversion scenario. U-235 is a fissile isotope of uranium, the stuff that would make a bomb (or a reactor) work. Slightly more than half of the cumulative total of the UF6, 96.3 kg, has already been fed into a conversion process to make reactor fuel, which is relatively benign, although any fuel not actually introduced into a reactor core or otherwise irradiated could be reconverted to UF6. Another 1.6 kg has been blended down, meaning it’s no longer enriched. A total of 91.4 kg is stored as UF6 and is therefore potentially available for rapid diversion.
For simplicity, let’s initially consider just the 91.4 kg of “up to 20% U-235” that’s in storage at last count. How close is that to a bomb’s worth?
Just 67.618% of UF6 by mass is uranium, so setting aside impurities, there’s about 61.8 kg of uranium in there. Most of that mass isn’t U-235, the fissile isotope. How much is? The enriched uranium is being produced at two sites, PFEP and FFEP. According to GOV/2012/37, back in early April, as part of an investigation into certain irregularities discussed earlier at ACW, Iran disconnected the product cylinder at FFEP, allowing the IAEA to verify the enrichment level. It turned out to be 19.2% U-235. If the PFEP product is enriched to a little more than that, then the overall result could be slightly higher, but using the 19.2% figure for the overall calculation gives us 11.9 kg of U-235.
In practice, a bit less than that would be available for a weapon. Re-enrichment would involve the loss of some of the U-235 into the tails (i.e., waste) stream. Exactly how much would be up to the Iranians. Achieving a smaller “tails fraction” would require more time to complete the work of re-enrichment. Presumably, they wouldn’t select a tails fraction that would put that first bomb out of reach. But just to account for this issue, let’s round down to 11 kg of U-235.
And what if we throw in the converted product? As mentioned above, GOV/2012/37 says that 96.3 kg of the “up to 20% U-235” UF6 has entered the conversion process for fuel. Fig. 8 conveniently states how much of that is already irradiated or is in the core at the Tehran Research Reactor, and is therefore unavailable for the scenario we’re contemplating. The total comes to 3.375 kg of uranium (not UF6). Following the same calculation above, we get 96.3 kg of UF6 * 0.67618 = about 65.2 kg of uranium. Subtracting the above-mentioned 3.375 kg of uranium leaves about 61.7 kg of uranium. This 61.7 kg * 0.192 = about 11.9 kg of U-235, coincidentally.
Not only would this total be subject to losses from re-enrichment, but it would face additional losses from conversion in both directions, since a certain amount of material gets “held up” in the system. (Ultimately, of course, these “process losses” would also apply to conversion to metal after the re-enrichment is done, and a bit would be left over after casting into hemispheres, too.) For convenience, let’s say that we’re left with just 9 kg of U-235 in UF6 form after re-enrichment.
Adding that to the estimated 11 kg sums to about 20 kg of fissile U-235.
How much is a bomb’s worth, anyway?
The IAEA considers 25 kg of U-235 to be one “significant quantity,” i.e., a bomb’s worth, but as Cochran and Paine have explained, and as Dalnoki-Veress, Lewis, and Pomper have already discussed extensively, this figure is much too high in almost all contexts. At this point, of course, it would be nice to know something about Iran’s bomb design. If anyone is sufficiently inclined, there might be enough information in GOV/2011/65 (the November 2011 report) and this article in Der Spiegel to take a stab at the question of how much fissile material it takes.
But to make a long story short, Cochran and Paine estimate that a relatively low-tech bomb program would need between 8 and 16 kg of U-235 for a pure fission weapon (an “A-bomb”), depending on how much explosive yield is desired. A medium-tech program, which is perhaps where Iran fits thanks in part to the foreign assistance described in GOV/2011/65, would need between 4 and 9 kg of U-235.
As a reminder, Iran already has about 11 kg of U-235 in the almost-20% U-235 UF6 that’s sitting in storage, and about 20 kg of U-235 available if you throw in other material that could be turned back into UF6. What’s more, GOV/2012/37, the source of the UF6 numbers above, is already out of date. As Table 3 of the report shows, more UF6 enriched to almost 20% U-235 is accumulating rapidly.
The bottom line is that Iran probably has enough material on hand today to support the breakout scenario that Israeli officials reportedly fear is coming within months.
On to the next artificial threshold of capability!
Not an engineer, so would the mid range bomb design be considered 100% reliable or would a test be required? I assume the basic design is overengineered to make non-component testing unnecessary.
Assuming the reports of the R265 design are accurate, and real (not a sophisticated frame-up job), and that the Parchin and other test reports are also accurate, by early 2004 the Iranian muclear program was able to report to the Supreme Leader that they had high confidence in the design working militarily.
If the design includes boosting and high (100 kt plus) yields that would remain untested, but basic operation at tens of kilotons in pure fission mode could be almost guaranteed. With high-enriched Uranium bombs, the test can be essentially 100 % accurate as to implosion behavior using natural or depleted uranium instead.
If you use the right test and diagnostic methods to check the results then the nuclear reaction modeling is not trivial but a well known straightforwards engineering exercise for heavier bomb pits. Final yield would remain uncertain but one could with high confidence predict yields would be at or above a large fraction of theoretical maximum.
It’s not as easy a question as gun-type bombs ( which the US built seven models of with only one test for the first model then two of the last… And used the first model in combat as its test…). But it is credibly easy.
The historic track record is that everyone who ever attempted to build a basic fission weapon got it pretty much right the first time, with the exception of North Korea and possibly Pakistan. So, even without all-up testing, Iran could be ~75% confident of full design yield and ~90% confident of at least high sub-kiloton yield with the first combat use of a hypothesized breakout nuclear weapons system.
100% reliability, that definitely requires testing, in the sense of actual nuclear explosions. Even if someone were to sell the Iranians the complete design drawings and manufacturing instructions for a tested nuclear weapon, they wouldn’t be able to get above 99% confidence without a test.
And perhaps most importantly, an awful lot of what are referred to as nuclear “tests” are not really tests at all, but demonstrations. If the goal is deterrence, or for that matter intimidation, it doesn’t matter how reliable your bombs actually are or how confident you are in their design; what matters is how confident your enemy is that your bombs will work. So, even with a 100.00% reliable weapon, the Iranians may need to set one off to accomplish their goals.
Whether a bomb that the Iranians know to be 75-90% reliable and the rest of the world can only guess at, will serve Iran’s needs, is for Iran to decide. Israel has maintained an effective deterrent with such weapons for thirty or forty years, but Iran may have different requirements.
> If the design includes boosting and high (100 kt plus) yields that would remain untested, but basic operation at tens of kilotons in pure fission mode could be almost guaranteed.
Other than the uncertainty in yield on the upper end, would there be any downside to building a bomb with an unboosted yield of X kt and accepting any boosting enhancement as a bonus? That would somewhat limit the weapons applications, but some shouldn’t be too sensitive to up-side yield uncertainties.
According to a JASON I once had lunch with(*), the physics of boosting is not as straightforward as it might seem at first. So, as you say, a couple of nuclear tests would probably be needed to gain confidence in the yield.
(*) At the American Cafe in Tysons Corner. You hear the darndest things in the restaurants around there.
Allen asks:
“Other than the uncertainty in yield on the upper end, would there be any downside to building a bomb with an unboosted yield of X kt and accepting any boosting enhancement as a bonus? That would somewhat limit the weapons applications, but some shouldn’t be too sensitive to up-side yield uncertainties.”
—
Short answer? Unless you get stupidly clever, with robust HEU devices, no downside I know of or can articulate.
Stupid clever is a recurring failure mode of the excessively bright but the Iranian device reminds me of a friends recent comments about the early Sidewinder missile as “the epitome of the 80% solution”.
Thanks, for the education, and sorry for the 100% comment. “Reliably Deployable” would be the level I was asking about. It sounds like they’re reasonably there for a nuclear Iran if Iran wanted it. So this is just arm twisting and politics on the PM’s part.
Cameron:
“Thanks, for the education, and sorry for the 100% comment. “Reliably Deployable” would be the level I was asking about. It sounds like they’re reasonably there for a nuclear Iran if Iran wanted it. So this is just arm twisting and politics on the PM’s part.”
They’re reasonably there, yes.
R265 plus Parchin test chamber and related test allegations form a picture which is incomplete but technically viable as a design and internally consistent. The weapon would fit in missile warhead sizes they already have (both size and weight) and could be used in an air-dropped bomb. It is just slightly too big for Iranian 533 mm torpedo tubes on their submarines.
Iran has suggested it’s a fake or fraud, not really what they have done. I cannot disprove that, but it would have had to be a creative nuclear weapon state faking it, who already knew about Danilenko, and Parchin. I personally feel it’s real, but acknowledge that the state of the public information is insufficient to prove either way. It seems unlikely anyone would use a viable design to frame someone like that, but that feeling is not proof that it’s not a frame.
“The bottom line is that Iran probably has enough material on hand today to support the breakout scenario that Israeli officials reportedly fear is coming within months.”
And is that supposed to reassure the Isrealis, or the opposite?
It’s meant to convey that the threshold now being discussed by Israeli officials, according to David Makovsky and Chuck Freilich, is just as irrelevant as past thresholds. I think all of these red lines, to the extent they are even definable, are essentially arbitrary and not connected to any serious attempt to grasp Iranian intentions. For example, just what would one do with a single bomb’s worth of HEU and an untested bomb design?
The point has often been made, here and elsewhere, that nuclear breakout is more fundamentally a risk-high political choice than a technological threshold. I believe that this point is understood very well in many places, including in Israel, but not necessarily by all members of the Israeli political class. Some of its members instead seem to have convinced themselves that Iran is (always) just about to turn a corner in terms of capabilities and burst into action.
PM Netanyahu and DefMin Barak seem to believe above all else that it’s dangerous to neglect the worst case. It turns out that there are dangers to being caught up in the worst-case perspective, too.
Personally I wonder if, as the technological development in newer nuclear-armed states recapitulates that in pioneer states, so will political and philosophical development. It is possible, for example, that Israel and Iran would find themselves equipped and inclined to pursue a strategy of de facto mutual assured destruction.
In that case, it seems to me, the proximate hazard would be not an Israeli attack on Iran, but pressure by the Shiite street on the Iranian government to encourage an attack on Israel.
Jeffrey,
As long as you have your slide rule out, how long would it take to convert the 90+ kg of 20% UF6 in Fordow to lets say 9 kg of 90% UF6 using the centrifuges in the facility if instantaneously reconfigured for 20% to 90% enrichment? My off the cuff calculation — 3 to 8 weeks.
How long would it take to convert 90% UF6 into a “Parchin Pit” of metal? My guess – an additional 3 weeks. One can make the assumption that everything else would already be in place waiting for the pit.
Is the plant for the conversion of UF6 to metal only as Isfahan, or could this be done elsewhere on a smaller scale secretly?
Am I off on my conversion time estimates?
Seems to me at this point the red line is: 1) any reconfiguration of centrifuges for breakout; 2) any diversion of UF6 stock out of Fordow or the PFEP at Natanz; or 3) any interference in the ability of the IAEA to detect and report on the above within 1 to 3 days.
Any idea on how much delay there would be on the IAEA detecting such an event, i.e. how often is an inspection done to verify the above?
Any idea on the false negative rate of the IAEA detecting a stock theft, substitution, or surreptitious reconfiguration. We have all seen plenty of art theft movies where the thieves substitute a video tape of the “pink panther” under surveillance by guards with a tape from a different day. What is to stop a “switcheroo” of the 20% UF6 stock for some natural uranium UF6 so that the remaining conversion can happen elsewhere.
Finally, we have read that the IR-4/5/6 units all have operational “problems” at the declared sites (primarily the PFEP). Is there anything that proves that this itself is not a subterfuge, such that a small number of more modern and much higher (SWU) centrifuges could be hidden somewhere else to enrich the 20% stock to weapons grade. (I.e. in a smaller building with a much smaller satellite intelligence footprint, perhaps in a major population center to act as an additional deterrence against attack.)
-Anon2
It’s a guest post! I am not doing any math, just burping a baby and changing his diapers.
Jeffrey,
Congratulations!
I will attempt to block out a few hours to do the SWU calculations and write them up — maybe by Tuesday, unless someone else here can do it faster. I don’t have any real idea on the process technology to convert UF6 to metal.
Anon2
@ Jeffery: That’s a dangerous redline you’ve crossed there!
@anon: It’s been a while since I’ve looked at this in depth, but as I recall the process is UF6 -> UF4 -> UO2 which is then cooked in a reduction furnace (known as a bomb reactor, really!) until it reduces to Uranium metal. If I recall correctly, you mixed powdered UO2 and either aluminum or magnesium powder in a very strong cruicible and then slowly heated it until the whole load reacted at once. The oxygen would hop from the Uranium to the Mg or Al in a basic thermite reaction, leaving very pure uranium metal. When this was being done at Fernald the resulting product was a billet of round metallic uranium called a Derby. The best resource I’ve seen for explaning this process is the book “At work in the fields of the bomb” by Robert Del Tredici which does an excellent job of explaining the conversion process.
For reactor fuel the preferred form is UO2, so it’s safe to assume the Iranians have plenty of experience getting it to that point. The further reduction process is chemically fairly simple, but I think somewhat more challenging in terms of engineering just to keep it from blowing up in your face (literally). I’m sure somewhere in Iran it has been done on a laboratory scale just for purposes of basic metallurgy,but whether the have a plant for doing it on larger scales is a good question.
As for the Israeli statement, it would be just as accurate to point to a pile of natural Uranium ore and say that there is enough uranium in there for dozens of bombs. It’s technically true, and only a little more misleading that what was actually said.
Jeffrey,
Great news. How are baby and mom?
And what’s the baby’s handle?
MK
@Jeffery – congratulations, we always need more boys in the world.
lets hope they don’t go pedal to the metal.
This scenario describes LEU “being raced out of storage to one or more hidden sites where it would be re-enriched to weapons grade and then fashioned into a bomb” i.e. secret enrichment and conversion facilities.
The first question is: if Iran had such secret facilities, and it had confidence in their secrecy, why not enrich and convert from scratch there, using uranium from its mines? Yes, it’s risky to breakout in secret. But breaking IAEA safeguards through the removal of LEU from a known site and taking it to an unknown site is tantamount to breakout out in plain sight. (One answer, that this would take longer, seems unsatisfying – if the facilities are ready to receive LEU then they are anyway presently at great risk of detection through human sources).
Second, is it not very difficult to safely and secretly transport ~190kg of 20% U-235? How would it be removed from Fordow without detection through satellites, and would there not be a very high risk of the movement of such material also, if traced, giving away the location of the secret site to which it is being transported?
Shashank writes:
“The first question is: if Iran had such secret facilities, and it had confidence in their secrecy, why not enrich and convert from scratch there, using uranium from its mines? Yes, it’s risky to breakout in secret. But breaking IAEA safeguards through the removal of LEU from a known site and taking it to an unknown site is tantamount to breakout out in plain sight. (One answer, that this would take longer, seems unsatisfying – if the facilities are ready to receive LEU then they are anyway presently at great risk of detection through human sources).”
This has to do with the math of how enrichment works. Because initial enrichment (natural U 0.7%) is so low that the bulk of the effort – measured in units known as kilogram separative work units (usually SWU), which you can think of as analagous to Centrifuge-years of enrichment work. Good centrifuges do ten KG SWU per year, say.
Once you enrich a bit, the volume you are processing drops. The initial enrichment takes nearly all (90%) of the work.
If one wants to break out, then, it’s far easier to have a big public centrifuge facility and then small secret one to finish it off.
“Second, is it not very difficult to safely and secretly transport ~190kg of 20% U-235? How would it be removed from Fordow without detection through satellites, and would there not be a very high risk of the movement of such material also, if traced, giving away the location of the secret site to which it is being transported?”
We are talking about one or a very few drums of material, which is not yet radioactive. One pickup truck, easy to miss, not practically traceable from orbit. Not unsafe to move.
George,
Thank you for your reply.
On the first of my questions: I see that the lag time is greatly shortened by using partially enriched uranium. But the notion that this is a less risky approach assumes that detection risk is principally a function of time taken to enrich. I am not so sure this is the case.
The point of greatest vulnerability w.r.t. to detection lies in the act of diverting safeguarded material. Although the precise details rest on inspections schedules, diversion would be recognized in a short period, and would be met with a military response against, at the very least, known sites.
The secret sites to which material is diverted will either remain secret or will not. If they do not, then the sites will get attacked as soon as the diversion is detected – negating any time saved in using partially enriched uranium. If they do remain secret, then why does it matter that you take much longer because of the initial enrichment time?
Forgive me if I’ve misunderstood. Thanks,
It’s more a question of the size of the facility than of time.
Using slightly made up numbers…
If 90% of the work is done elsewhere (reactor grade to weapons grade) by 8000 centrifuges in Natanz and Fordow then a whole-stream final site is 800 centrifuges, a third of Fordow or a sixth of Natanz. If it’s 95% done elsewhere or more (20% to weapons grade) then that’s 400 centrifuges, etc.
Eventually it stops being a major secret base and becomes a single secret basement, or side shaft in an old mine or the like. Something small enough that construction doesn’t raise flags on satellite view, or no new construction is required. Then it’s up to an intelligence break about the location…
Note that even Fordow’s nature was kept secret until a lucky intelligence break involving inside information; the scale at which a centrifuge-based enrichment program becomes inherently vulnerable to discovery by its logistical footprint is disturbingly large.
And speed still matters, because the issue isn’t just detection risk, but detection consequences. As noted in Jeffrey’s orginial post, Iran already crossed every meaningful red line months ago, and the consequences are not that Iran is being bombed, but that people are talking about how maybe someone will maybe bomb Iran in a couple more months. So, yes, if a truckload of Iranian soldiers show up at an IAEA-safeguarded site and drive off with a bunch of enriched UF6, detection is certain.
And, presuming even marginal competence among Iranian diplomats and propagandists, inconsequential for the next three months or so.
Meaning, it makes a big difference if Iran actually can go from a bunch of reactor-grade UF6 to a deployed nuclear arsenal (plus maybe a demonstration shot) in three months or less. By the time anyone is ready to do more than talk about bombing Iran, they are in a position to deter anything less than a deliberately and mutually apocalyptic response. This is the classic “breakout” scenario, and it is a real worry. Particularly if it turns out to be a close race, and the US/UN/NATO/Israel guess wrong as to whether Iran’s nuclear arsenal goes on line tomorrow or yesterday.
Another aggravating factor of large stockpiles of reactor-grade LEU is hidden in that bit about “diplomatic competence” above. If Iran at least pretends to have a civilian nuclear program requiring LEU, even the discovery of an actual secret safeguarded enrichment facility busily producing tons of undeclared LEU can be spun as “we were just trying to secure our critical national power/medical resources against you nasty warmongers and your JDAMs”. That was, in fact, Iran’s fallback plan when Fordow was discovered, and it bought them a lot more than three months.
Discovery of a secret stockpile of weapons-grade uranium, or facility busily producing same, that is one of the few things that plausibly gets Iran bombed without months of preliminary debate, so they would want to minimize the period in which such exposure is possible.
John: One of the differences between your scenario and Fordow is that Fordow wasn’t “busily producing tons of undeclared LEU” – it wasn’t operational yet, so they were able to say “Oh, we were totally planning to declare that plant before we started introducing nuclear material into it”.
Now one can argue as to whether they really were planning to do that or not, but that argument wouldn’t be available to them at all in your scenario, which makes it substantially different.
I second kme and note that Iran has not broken its self-declared obligation (as per Code 3.1 of the Subsidiary Arrangements) to inform the IAEA at least six months before nuclear material is introduced into its enrichment facilities. This was the case in both Natanz (where Iran was absolutely innocent) and Fordow (where the matter is legally disputed but nevertheless Iran was within its original obligations).
George:
I take your point, but I’m not sure this addresses the central concern, which is that there is a 100% chance that diversion of safeguarded material will be detected – as against a less than 100% chance that parallel enrichment will be detected.
Yes, a smaller facility that simply takes reactor-grade LEU is more easily concealed. But if you balance the risk between a larger facility which has to do more of the preliminary enrichment, and a smaller facility that that requires breaking safeguards, then it still seems the former would be more desirable.
John:
I don’t see why detection would be “inconsequential for the next three months or so” [presume you meant the three months after detection?]. Aside from some rudimentary efforts with the IAEA board and UNSC, I think you would very likely see military action in under a week. I don’t see the US or Israel spending a lot of time fretting over Iranian propaganda over how such diversion is for defensive purposes etc.
Shashank:
“I take your point, but I’m not sure this addresses the central concern, which is that there is a 100% chance that diversion of safeguarded material will be detected – as against a less than 100% chance that parallel enrichment will be detected. Yes, a smaller facility that simply takes reactor-grade LEU is more easily concealed. But if you balance the risk between a larger facility which has to do more of the preliminary enrichment, and a smaller facility that that requires breaking safeguards, then it still seems the former would be more desirable.”
The situation is time-dependent. The natural to LEU enrichment facilities are larger, but if declared they operate openly for any length of time and build up large enriched inventory.
If or when Iran breaks out, safeguards are broken, that pre-readied material goes off to tiny secret Site C and bomb cores start rolling out.
For Natanz or Fordow to do that requires both intent and process changes to at least one cascade, to input LEU. Sute C is spinning under vaccum just waiting for 20% or reactor grade fuel input.
If they declared breakout and diverted material but only had Fordow and Natanz, we know where those are and could bomb.
Site C might be deep and hardened enough to be practically invulnerable, and in a secret location. Even if it was located it might not be bombable.
Once the feedstocks reach this quantity rhen there is no way the west and Israel can trust that any intervention necessarily can work.
Jeffrey,
Thank you for opening up this topic!! I have been eager to see some technically informed strategic discussion of this.
My small technical contribution: to make 10 kg of 93% enriched U from 19.2% enriched feed can take either 53 kg of feed and 136kg-SWU with 2% enriched tails, or 82 kg of feed and 87 kg-SWU, with 9% enriched tails. About a factor of 1.6x more feed for about a factor of 1.6x more SWU. (An ideal SWU calculation, of course.)
The Sept 4’th Jerusalem Post quotes Emily Landau of INSS as advocating a red line at 20% enrichment, which makes more sense to me. But drawing any red line carries lots and lots of implications. I would love to see expert discussion of this topic.
You will remember what it is like to sleep thru the night in 4 or 5 months.
– Rob
I should have said “a factor of about 1.6 more feed for a factor of about 1.6 less SWU”, of course.
Correction: I should have said “a factor of about 1.6 more feed for a factor of about 1.6 less SWU”, of course.
I have already published calculations on this issue at NPEC. The latest IAEA report gives contradictory info on how much 20% material has been converted U3O8 so Iran could have either 79kg or 62kg of 20% UF6. Assuming Iran has built a clandestine enrichment plant that acts as an ideal cascade then Iran could produce 16.8kg or 13.2kg respectively of HEU. Nor would Iran have to stop there. It could convert more of its 3.5% enriched uranium to 20% enriched uranium and then to HEU. It could produce over 80kg in about 6 months with a reasonably sized clandestine plant.
Even if Iran doesn’t have a clandestine enrichment plant it can batch recycle at the existing facilities and produce 20kg of HEU in about 10 weeks. It is small wonder that I think that Iran is already a defacto nuclear weapon state, something that the title of this post originally said before it got consigned to the memory hole.
Iran doesn’t have to even “breakout” to produce the HEU. Maybe it will decide to produce some HEU to start work on its naval propulsion program. The IAEA will gladly safeguard the HEU until Iran gets around to trying to build the naval reactor (which could easily be decades away).
Just to be clear I don’t think that Iran will actually produce nuclear weapons anytime soon. Why should it? Everything is already going it way.
If Iran was so hellbent on nuclear weapons, why suspend enrichment entirely for almost 3 years? Why allow “inspections” of facilities way outside of the IAEA’s jurisdiction, like at Parchin (twice.) Why offer to cap enrichment and to operate their program as a joint multinational enterprise on Iranian soil? Why agree to ship out 1200 kg of LEU, only to have the US kill the deal after Iran said yes? Are these things that a country seeking even “breakout capability” would do?
“If Iran was so hellbent on nuclear weapons, why suspend enrichment entirely for almost 3 years? Why allow “inspections” of facilities way outside of the IAEA’s jurisdiction, like at Parchin (twice.) Why offer to cap enrichment and to operate their program as a joint multinational enterprise on Iranian soil? Why agree to ship out 1200 kg of LEU, only to have the US kill the deal after Iran said yes? Are these things that a country seeking even “breakout capability” would do?”
They are continually adding more centrifuges and repairing old ones, and building up more enriched product.
They gain nothing in any sense from breaking out early. It only makes sense once they are in convenient reach of weapons, between stock buildup and centrifuge capacity buildup.
It’s down to months of work if they decide to do it now, which was the point. But there has been a steady march up here with open disclosure and IAEA stock monitoring. So it’s not a surprise or shock, which was the other point.
Cyrus:
– Enrichment was not “entirely suspended”. Construction of centrifuges continued.
– Why “allow” inspections? Because Tehran wants to maintain the fiction of an entirely peaceful program. (And why not allow another visit to Parchin? Hmmm…)
– The “offers” you mention were just… offers., never concrete proposals.
– Iran only agreed to ship out the material after it
had produced much more than the 1200 kg; and the declaration included a provision which basically allowed Tehran to take it back at any time. All this killed any possible deal from the point of view of the P5+1 (not only the US).
Nobody (at least not me) would say that Iran is “hellbent” on producing nuclear weapons.
What Shaheen said.
At a time when Iran said and the rest of the world believed that Natanz was Iran’s sole enrichment facility, Iran in fact built a covert, hardened 3000-centrifuge facility at Fordow. In that era, Iran demonstrated the ability to manufacture ~3000 IR-1 centrifuges per year. And if my math is correct, Iran has over the past two years installed a total of ~3000 centrifuges at Fordow and Natanz combined.
A suspicious individual might be forgiven for believing that there are now ~3000 centrifuges installed in a facility that is neither Natanz nor Fordow and has never been inspected. That would be about enough for one bomb’s worth of HEU per year from scratch, or one every two months from 20% feedstock, whichever and whenever they might like.
That same suspicious individual might also believe that Iran’s R&D work at Parchin through 2004, might have produced a preliminary design for a nuclear weapon which has since been shipped to a place which is Not Parchin.
Were I in charge of a nuclear “breakout” program so constituted, I would be happy to suspend operations and allow inspections at Natanz, Fordow, and Parchin. Ideally with a level of protest calibrated to consume the West’s available diplomatic bandwith on arranging just those inspections and leaving them satisfied they had won a great but difficult victory on the field of nonproliferation. Shipping some of the acknowledged LEU out of the country, that would be undesirable but tolerable, particularly if the effort to arrange it keeps the West suitably distracted for a few years.
But I’m not running Iran’s nuclear program. I’m on the outside, looking in. And I’m suspicious.
What John Schilling said.
John Schilling,
Did Iran ever say unequivocally that Natanz was its sole uranium enrichment facility? As far as I remember, Iran has long argued that it’s not required to announce the existence of such facilities before six months to introducing nuclear material into them.
What are the quantities of 90% HEU needed?
“Classical” implosion using a full HEU pit is about 20kg. Using hollow pits you get higher compressions, so the quantity is less.
Extrapolating from Plutonium (2kg minimum, 6 kg maximum), and considering that HEU fast fission crossection is about 3 times smaller, this comes to about 6kg minimum to 18kg maximum for an implosion system.
From US and USSR history, we also know that you need at least three bombs worth of fissile material before you go public, so the quantity of HEU will vary from 3 x (6kg to 18 kg, or 18 to 54kg of 90% HEU. If you add the material lost in processing, add another 20%…so we are talking about 21 to 62kg for 3 weapons. They’ll have to be conservative, so I’ll be inclined towards the higher quantity, say about 60kg…
Iran already has a 20% stockpile sufficient to meet the above quantities, so it’s a question of how quickly they can enrich it to 90%. The reduction to metal, casting and rolling, etc. takes about 2 to 3 weeks for Iran’s level of technical capability.
The answer here depends in detail on implosion system performance analysis and optimization that frankly should not be posted in detail in public.
All I want to say now is that it’s not looking like it’s solid core. The Parchin chamber info implies volumetrically half HE half pit or hollow.
Readers might want to consider the implications of the smaller Pakistani design that surfaced in the care of the Tinners.
http://lewis.armscontrolwonk.com/archive/1916/pakistani-design-in-switzerland
Hi guys. I am just a citizen, not a nuclear professional.
Isn’t the real question here what would a bomb be used for? If the goal is to wipe Israel off the map, a bigger boom is better. But if the goal is the “extinction of the Zionist Regime”, AND the return of Palestinian lands to the Palestinians, then smaller, tactical booms might actually be better. If you make Jerusalem uninhabitable, in the eyes of the Muslim Ummah, what have you really accomplished?
Similarly if you want to intimidate neighbors, a tactically sized nuke could wipe out Saudi desalinization plants and oil infrastructure as well or better than a huge cloud with unpredictable downwind consequences. If you want to declare the Gulf a US free zone, small nukes might prevent a MAD sized US retaliation.
In terms of the end use, very small nukes accomplish 90% of what Iran may wish to accomplish. The ICBM mindset may be a US imposed framework, not an asymmetric mind set.
No Iranian size strategy for nuclear weapons would avoid massive retaliation if they fire them at someone else’s territory.
Nuclear warfighting, in the tactical sense, is strategic folly.
That is not to say that large sophisticated nuclear arsenals aren’t diversified, but Iran using its own weapons other than as a deterrent in waiting or perhaps defensively on their own territory is the end. The people they might offensively nuke will nuke back, period. If they think otherwise they would be suicidal madmen.
@George William Herbert | September 19, 2012
“Nuclear warfighting, in the tactical sense, is strategic folly.”… and a big “boom”, “wiping” both Jerusalem and the Palestinians “off the map”, would also be out of the question considering Israel and probably most other potential enemies have second strike capability.
So, why would Iran even want nukes or a nuke “capability” other than for deterrence? Wouldn’t that make good sense in a neighborhood with several nuclear hosts already and at least one nuclear “guest” refusing to rule out a first strike prerogative?
There is deterrence, and deterrence.
“If you nuke me I nuke you” is one form.
“I have just invaded Saudi Arabia and you will not intervene or interfere, because coincidental 20 kiloton nuclear test” is entirely another.
Iraq was attempting to do that with Kuwait in the 90s. They were going to attempt a nuclear test with available, diverted HEU stock before Desert Storm made it a moot point.
GWH, that is certainly the current paradigm, at least until it changes.
If you are going to put a toe over the nuclear threshold and get away with it, it would have to be a very small toe. Nuking Tel Aviv, or threatening to do so, might make Iran the hero to 1.5 Bil Muslims. Turning Tehran to glass might guarantee a 50 year war with all of them? The warfare paradigm could change quickly.
Until and unless Iran develops missiles with enough throw weight, any weapon developed now would, by default, be used in an asymmetric way. The development of a 1, or 3 or 6kt weapon may accomplish what Iran currently needs from a military, political and deterrent effect. Their first ambition is to be a regional superpower. It is a Western mindset that has determined that 25kg of Uranium is the step off point. As Jeffery so well stated, we are already there technically. We may also be there ideologically.
Thant’s not to say that Iran will not push it’s capacity under the watchful eye if the IAEA, but after a point, it is all just gravy.
I’m reading between the lines here, so apologies if I’m wrong, but it seems that you think that a less powerful weapon can be made by simply using less HEU.
That’s not really how it works. Designs that are efficient in their use of fissile material are significantly more technically challenging than a basic design. As the mass decreases the amount of compression required increases sharply. There’s a practical lower limit on the amount of fissile material required.
“Until and unless Iran develops missiles with enough throw weight,”
—
They already have those. Sejil, Shahab-3, Ghadr-110, etc.
All their triconic missile reentry vehicles are highly suspect as intended to be R265 carriers.
Ok, but even the most crude clumsy overweight device could be put on a fully loaded Suezmax in international waters 12 miles from Tel Aviv and driven onto the beach. (My apologies to Tom Clancy) We are constantly fighting the last war. On 9/10/2001, absolutely no one thought two skyscrapers in the middle of New York would fall the next day. Our enemies think out of the box better than we do.
ANY sized operable nuclear device is a potential game changer. Everyone is calculating the SWU to 25 kg, thinking that produces one bomb. What if it produces four? How fast could Iran spin up 6 to 8 kg of 90% Days, hours?
We crossed the red line for a tactical device months ago.
Warheads or bombs don’t scale fissile material needed like that. Half the material is not half the yield. For a given implosion system technology and size you need some minimum amount, then yields go up rapidly. Half the 20 kiloton fissile amount probably is no yield to speak of.
As for terrorist bombs… Yes, if Iran wanted to drive a ship or boat ashore near Tel Aviv with a nuke, that’s a risk. But Iran can’t park that ship in the Med and ask Israel not to threaten them, using it to deter an airstrike. Israel would board every possible ship, find and disarm the bomb. And under the circumstances nobody would object. It would be seen as an aggressive act as well as being acutely vulnerable to interception. They can’t covertly place a ship there to deter; it has to be known to deter. They can’t start a war and then sail the ship there, everyone would be looking for it thrn.
Terrorist like strikes are inherently only useful as first strikes. Iran presumably understands that doing that results in their destruction by Israeli, US, and probably French and English nuclear responses. We ( the community of proliferation experts ) presume that’s not their goal.
If credible evidence surfaced that it was, we’d be at war with them by the end of the week. Nuclear programs in such persons’ hands are unacceptable, no matter the conventional cost.
The presence of nuclear capable missiles is a strong sign of deterrent use intentions. Nuclear missiles are excellent tools of deterrence. Silos or shelters are easy to defend, not provacative, on the owners own territory, hard to intercept. It’s a sign of inherently deterrent intention.
But as I said, deterrent can be passive or used to cover conventional warfare aggression. Or conventional missiles to Hamas and Hezbollah, blowing up ambassadors and cultural centers.
To paraphrase:
A program aimed at nuclear weapons, begun out of fear, is rational, sane, and met by diplomacy intent on off setting the benefit of strategic military security with economic and political consequences.
A program aimed at nuclear weapons, begun out of anger, is like a rabid dog in an elementary school. You kill it not because you hate it, but because the danger of its existance is to great.
As for delivery systems, IC/MR-BM use is trackable to the country of launch from the time of launch. You can’t use them and expect your regime, and perhaps your country, to survive. As George Herbert pointed out, they are great for deterrance.
I disagree that a terrorist first strike is the way to go either. It’s not like possible culprits are lining up around the block, and it’s likely Israeli decision makers nre not going to be in the mood for a long discussion.
Thank you all so much for this post and these comments. To those of us who don’t understand the technical issues and have only the politicians to listen to as we try and sort out what is happening, this discussion is pure gold.
@Jeffrey: “just burping a baby and changing his diapers.”
I am interpreting this, and the responses to it, as an indication that you now have skin in this non-proliferation game. That is the single most optimistic piece of information I’ve seen for well over a year. Big Lebowski fans might recall the Stranger’s closing soliloquy: “I happen to know that there’s a little Lebowski on the way. I guess that’s the way the whole durn human comedy keeps on perpetuatin’ itself . . . down through the ages, westward ho the wagons.” Here’s to the hope that you and the Stranger are both right.
@George: “I have just invaded Saudi Arabia and you will not intervene or interfere, because coincidental 20 kiloton nuclear test” .
Bingo. Operation Samson I think this is called. This was precisely Golda Meir’s tactic when she forced Nixon into the Yom Kippur War with her threat that she would nuke Cairo if the US didn’t get the Egqytian MIGs off her backside. People keep saying that the US is the only country to ever “use” a nuclear bomb. Not true. You don’t have to detonate one in order to use it.
@George: Israel would board every possible ship, find and disarm the bomb. And under the circumstances nobody would object.
Bingo II. You sure got that right judging from the way the international community stifled a collective chuckle when Israel boarded the unarmed peace ship Mavi Marmara and snuffed 9 peace activists with head-shots, including an American.
@George: Terrorist like strikes are inherently only useful as first strikes.
Disagreement. I think by “useful” you are referring just to producing the initial damage. But the goal of terrorism, by definition, is not to destroy things and people, it’s to impose one’s ideology by frightening them with the threat of the destruction of things and people.
9/11 was incredibly, incredibly useful to the terrorists not [just] b/c they brought down their targets, but b/c they destroyed – and continue to destroy – so many of the principles and personal freedoms Westerners once thought were “God-given.” In August 1991 one would have had to be a George Orwell to have dreamed of today’s commonplace totalitarian monstrosities, like indefinite detention w/out charge or hearing or habeas corpus; presidential hit lists (much less those that include Americans); warrantless wire and GPS taps; & etc., & etc.
The terrorist attack of 9/11 was “useful” b/c the US today looks a whole more like al-Qaeda wanted it to look. al-Qaeda didn’t just win on 9/11, they’ve been winning every day since. By extension, a low-yield nuke built by or with the help of Iranian [or Israeli, or Pakistani, or …] technology/fissile material, delivered by U-Haul, and detonated in Peoria, Ill or Cumbria, UK, or . . . [insert any place] would turn the world into a totalitarian police-state that would make al-Qaeda look like the ACLU by comparison.
9/11 was incredibly, incredibly useful to the terrorists not [just] b/c they brought down their targets, but b/c they destroyed – and continue to destroy – so many of the principles and personal freedoms Westerners once thought were “God-given.”
The terrorists didn’t “take away” our freedoms, we voluntarily gave them up. There was no member of Al Queda in congress voting for the PATRIOT act, Osama Bin Ladin didn’t sign it into law, Hezbollah didn’t write memos saying that the US can detain anyone, including it’s own citizens indefinitely without charge. We the people, through our elected representatives, did this to ourselves. Terrorists can blow up buildings and kill people, but taking away freedoms; only we can do that.
Denis:
“Disagreement. I think by “useful” you are referring just to producing the initial damage. But the goal of terrorism, by definition, is not to destroy things and people, it’s to impose one’s ideology by frightening them with the threat of the destruction of things and people.”
—
Let’s talk what happens next.
Let’s differentiate terrorist (non- or sub-state actor) from terrorist-like (state actor).
A terrorist group has less to lose and is already difuse and hardened. Obviously retaliation happens, but the group cannot generally be bombed out of existence as it’s covertly entangled in civilian populations in some state. Based on 9/11, whoever does this has to expect to be martyred but may consider the goal worth that.
A nation-state has everything to lose; governmental control, territory, population, under these circumstances perhaps all of it – perhaps its very existence. Nations exist to protect their existence – doing something that would destroy themselves is contradictory.
Nations do not – as a rule – act like terrorists, because they have too much to lose. The exceptions around the edges do not – we think – extend to nuclear first strikes.
This is a big assumption, but as I said earlier, if we had evidence to the contrary about Iran we’d go to war promptly because that is simply not an acceptable safe situation for the world.
Iran’s grand strategy and goals are somewhat opaque, though widely hypothesized about. They seem sane and not the sort of thing we’d have to promptly destroy them for. That is not the same as friendly, but not signs of suicidally unfriendly.
George: “Nations exist to protect their existence”, yes, that is the ultimate expression of Pournelle’s Iron Law of Bureaucracy, but it takes time to kick in. First-generation nations can sometimes exist to serve an ideology or institution, even with literally suicidal determination. See, e.g., the Confederate States of America.
The Islamic Republic of Iran is a 1.5th generation nation-state, and one which has done a surprising ammount of nation-building and even industrialization, so this is hopefully just a nit. But people will legitimately worry about Iran doing things that e.g. China simply would not.
Dennis and Cthippio: It is easy to believe that if another’s deliberate act caused us great harm, it must have been intended to cause us harm. But for the most part, Middle Eastern terrorists simply don’t care how long we have to wait in airport security lines, or that we have gone from being a nation of proud individuals to meek sheeple, or whatever else gets your goat. Why should they care about such things, any more than we care about the price of bread in Cairo[1]?
They care about things that affect *them*, such as whether the leaders of their countries are brutal pro-Western dictators, brutal anti-Western dictators, liberal democrats, or Islamists dedicated to restoring the Caliphate. And I think you’ll find terrorists fighting for all of those goals, some more than others.
But they do what they do in support of *those* goals, hurting us only incidentally. If any particular group of them hasn’t yet achieved its preferred local political outcome, then it doesn’t matter that they have perhaps killed a hundred million Americans and reduced the rest of us to abject slavery. They haven’t won. And whatever it is they are doing, they aren’t done with that.
OTOH, if they can arrange to put their preferred brand of dictator or whatever on the throne without causing the slightest incovenience to Americans, even by incidentally making us all wealthy beyond the dreams of avarice, they’ll do that too.
It is unfortunately the case that Middle Eastern local politics is arranged such that the easiest path to certain forms of political change happens to involve dead Americans. But it is simply not the case that they “Hate Our Freedoms”, count it a victory when our liberty is diminished, or even generally want to cause us harm. If that is your model, you will not accurately predict their
behavior.
[1] They sometimes do care about the way such things are portrayed on their television channels, just like we care when someone plasters a bunch of starving Africans across our TV screens. But this generally doesn’t happen unless it serves someone’s local agenda.
@George: Let’s differentiate terrorist (non- or sub-state actor) from terrorist-like (state actor).
Herein lies the problem and, potentially, the fallacy. Making such a distinction is probably a necessary starting point, but I don’t think we want to rely on that distinction as the basis of a plenary or helpful analysis. The world is far more complex and dirty.
Having differentiated the rational state-actor from the irrational terrorist, one then has to allow for the fact that in many – most – situations it is an illusory distinction b/c irrational terrorists or terrorist organizations are often, if not always, proxies of one or more seemingly-rational states. The terrorists’ money, technology, arms have to come from somewhere, or they cannot function as terrorists. The terrorist carries out the (irrational) terrorism and the supporting state presents a rational face to the world.
The US is a pro at this game. Think “Contra” or “ARVN” or even “al-Qaeda” during the 1980’s. Israel (borderline irrational, arguably) is carrying out terrorism in Iran via MEK (a group on the US terrorist list). Iran, however rational it appears and claims to be, is a pseudo-terrorist [or maybe “potential terrorist” is a better term] country by virtue of its proxies, such as Hezbollah.
Because of all the smoke and mirrors, rational v. irrational does not map 1:1 to state v. non-state actor.
Would any one of the US, UK, France, Russia, Israel (“rational” actors) surreptitiously put a nuke in the hands of one of its (irrational) proxies in order to attain its goals while appearing rational? It’s hard to see that, but mostly b/c they wouldn’t have to.
Would Iran, Pakistan, or NoKo? Not so sure. IOW, if (apparently rational) Iran is at the break-out stage, doesn’t that make (apparently irrational) Hezbollah scarier?
I think we non-engineers would see this question as a matter of psychology while you nuke-wonks probably see it as a technical one. I’ll go with whatever you guys say: Could Iran physically transfer a detonation-ready nuke or an Ikea home-assembly version of same to Hassan Nasrallah without every spy satellite and drone in the sky lighting up? If the answer is “yes,” then where is the distinction between rational state actor and irrational terrorist from, say, Israel’s perspective?
Agree with George. Would add the following: to believe that the Israelis have not thought hard about the nuke-carrying-merchant-ship-in-Haifa scenario would be a very unsafe assumption to make if you were the IRI.
@Denis
Would add that the characterization of terrorist as “irrational”, i.e. not motivated by rational thought in optimizing their (the terrorist’s) best outcome is not true from the point of view of the terrorist.
The theory of terrorism is that using brute civilian terror to the population of a nation states can induce the nation state to behave in a way that they otherwise would not; or even to cause an outcome that is beneficial to the goal of the terrorist.
Thus, if Al Qaeda can induce through terror a Western country to use cruise missiles or drones to attack its operatives in a third party place like Pakistan; knowing that such attacks will have collateral damage that greatly harm some citizens of Pakistan such that they would cause riots that would kill Pakistanis who live in America and have come home for a visit, then Al Qaeda has effectively prevented Pakistanis from visiting America and then coming home and extolling the virtues of its free society.
Similarly, a nuclear weapon in the hands of a terrorist may encourage a permanent wedge between the country attacked and all such countries where the attacker may have come from such that it would not longer be possible for people to travel between the attacked country and multiple other countries. It may also discourage the nuclear attacked victim country from continuing one or other foreign policy.
I state that from the point of view of the terrorist this is rational; just like from the point of view of the Mafia killing to establish dominance in a territory is good business practice.
For the record, I despise both the Mafia and terrorists, both who effectively kill for their “business”.
Now that it appears that Iran is a virtual nuclear state and will progress on to being a turn-of-screwdriver away from nukes within a year or so, is this not the grand opportunity to go forward with the Nuke Free Middle East effort? Where all M.E. nations from Egypt to Iran would come under a rigorous AP implementation of the NPT? With Iran now becoming a nuclear power, is it not in Israel’s interest to accede to the NPT with AP and have all its nukes removed in exchange for a guaranteed nuke free zone?
Adding “Freak Out” at the end was HI-LAR-I-OUS.
the u.s.a., for years has been trying to get israel to do the dirty work:attack iran so they (the u.s.a.warmongers) won’t have too and condem israel for doing it. this started with President George W. Bush.