Michael KreponThe Triad

Amidst talk of budget cuts and further strategic arms reductions, the Pentagon has issued another ritualistic affirmation of the Triad in its report to Congress on Nuclear Employment Strategy. During the Cold War, the big plus of maintaining a strategic force posture consisting of bombers, land-based, ocean-spanning missiles and ballistic missile-carrying submarines was clear: diversification posed an insurmountable targeting problem for the Soviet Union. This rationale no longer keeps US taxpayers in thrall.

The big minus of paying large sums for the Triad was that it didn’t make Americans feel more secure when the Soviet Union chose three-way protection, as well. The reassurance that the Triad was supposed to provide was undermined by one of its legs. The prompt hard-target kill capabilities residing in intercontinental ballistic missiles fueled anxieties about surprise attack, driving warhead numbers up to assure massive retaliation.

The combination of sunk costs, Soviet competition, and strong domestic constituencies congealed US strategic force structure. In 1971, Herb York, who previously served as the Pentagon’s head of research and development, summed up the pros and cons of keeping the Triad in testimony before the Senate Foreign Relations Committee this way:

The maintenance of a triad … ensures that should any potential crisis emerge in the future, no adversary could conclude that any perceived benefits of attacking the United States or its allies and partners are outweighed by the cost our [nuclear] response would impose…

Our triad of weapons does present an extremely complex problem to the Soviets. It complicates the problem of making a preemptive attack on us. It complicates any plans they may have for defending against an attack by us…

It ought to lead to fewer weapons in total and it ought to eliminate frantic responses on our part to the notion the Russians may possibly be preparing for an attack against one of our [triad’s] components. In the real world, however, the triad seems to have exactly the opposite effect. We build and deploy each component in more than sufficient numbers to do the whole job… and we simultaneously inflate the size of the job and we do frequently respond frantically to Soviet moves…

So while the triad ought to lead to fewer total weapons than either a dyad or a single system, instead it seems to lead to three times as many.

Secretary of Defense James Schlesinger had a moment of candor when asked about the Triad during Senate Foreign Relations Committee Hearings in 1974. His questioner, Stuart Symington (D-Missouri), previously served as Secretary of the Air Force:

Senator Symington: [Dr. York] said he thought that we would not be moving on with the Triad if we had known all three systems would work.

Secretary Schlesinger: In my posture statement there is a switch away from what I will call the canonical logic of the Triad.

Senator Symington: My guess would be that he was worried about the efficiency of the Polaris-Poseidon syndrome development at that time.

Secretary Schlesinger: To some extent, I think the rationale of the Triad was a rationalization.

The US Triad was a product of atomic anxiety and service rivalry during the Cold War. It has subsequently survived a quarter-century of deep cuts, and is likely to survive longer. The biggest threats to the Triad in the United States aren’t budget cuts, new thinking about deterrence, or the continued shrinkage of the Russian Federation’s fortunes. Instead, the biggest threats to the Triad reside within the officer corps of the US Air Force and Navy. They won’t be getting out of the nuclear business, like the US Army, but they would prefer to spend money on and be assigned to weapon systems that have greater military utility.

Cruise missiles provide a sense of clarity on these matters. In the United States, cruise missiles evolved from being a bargaining chip in nuclear negotiations, to being projected as significant supplements to the Triad, to being dispensable for ground-basing in Europe, to being modest contributors to nuclear targeting plans. In military terms, a nuclear-armed cruise missile is good for only two things, neither of which can be commended for actual military utility: to cross the nuclear threshold or to serve as a radioactive rubble multiplier. In contrast, conventionally-armed cruise missiles have considerable military utility against targets on land and at sea. Portions of each leg of the US Triad have similarly been re-purposed to provide added military utility.

Elsewhere, the model of the Triad continues to have appeal. The Kremlin never had much of a bomber leg and, with its sea-based deterrent facing hard times, is recapitalizing its land-based missiles. China, India and Pakistan are working to add new sea-based capabilities to possess small-scale Triads. Even in the absence of prompt hard-target kill capabilities, the triangular competition in southern Asia shows no indications of tapering off.


  1. Robert (History)

    I’ve seen SECDEF Schlesinger’s quote on the triad used and abused far too many times.

    A strong supporter of the triad, Schlesinger made that comment during an exchange with Senator Symington, in which the former was lamenting, not the nuclear triad’s existence, but rather the triad’s historical lack of flexibility, selectivity, and counterforce targeting vis-a-vis the Soviets.

    The canonical logic that Schlesinger criticizes — not only in his Senate testimony but also in the FY 1975 DoD Annual Posture Statement — is that of countervalue targeting. Indeed, you omit the passage immediately above Schlesinger’s quote, in which the SECDEF says: “For reasons that I have indicted, I would not want to attack an urban industrial base. Therefore, I would want to have the capability to refrain from attacking an urban industrial base. _Fortunately, that is what a sophisticated strategic force does_….” (emphasis added).

    See Senate Foreign Relations Subcommittee on Arms Control, International Law and Organization, “Hearing on U.S. and Soviet Strategic Doctrine and Military Policies” (Washington, D.C.: U.S. GPO, March 4, 1974), esp. pp. 24-25. Also cf. FY 1975 DOD Annual Posture Statement (March 1974), esp. 49-66.

    • krepon (History)

      Thanks for providing the context for Secretary Schlesinger’s testimony missing from my post and from my 4X6 card.

      Dr. Schlesinger’s views on nuclear targeting became the new ‘canonical logic’ of deterrence, providing further justification for the Triad.

  2. Johnboy (History)

    I understand that the deployment of nuclear-tipped cruise missiles by the USA makes little sense because the USA already has ballistic-missile submarines i.e. their only job is to dawdle along in the wake of those missiles, by which time The Damage Has Already Been Done.

    But don’t they make sense to countries that DON’T already have that capability i.e. doesn’t the nuclear-tipped cruise missile appeals as a cheaper alternative to the ballistic-missile sub?

    After all, wasn’t that the rationale behind the Israeli procurement of those German built Dolphin-class submarines?

    • krepon (History)


      Your point is well taken.

      Pakistan, for example, has demonstrated interest in cruise missiles as an insurance policy against the possibility that India will decide to deploy BMD of some kind.

    • Patrick (History)

      I’m surprised there isn’t more discussion of this in the context of the UK debate over Trident. TLAM-N equipped Astutes seem like they’d give you 90% of the capability for 10% of the cost.

  3. Fred Miller (History)

    I’ve always been a little suspicious of the Strategic Triad. There’s no actual evidence that we are more secure with it. Like the Holy Trinity, you have to take it on faith.

    When our nuclear arsenal was entirely based on heavy bombers, did anyone declare the vulnerability of our “Strategic Monad”? Did any theorists give a reason that we needed exactly two more delivery methods? Or is the Triad simply a justification after the fact?

    If so, we should demand to see some justification for the Triad that demonstrates how an attack on the US could destroy a strategic duad or monad so thoroughly that we could not inflict unacceptable losses in retaliation.

    When we don’t have enough money to maintain our economic infrastructure, protect our environment or even raise and educate our children, maintaining a Strategic Triad for reasons that are largely bureaucratic and political is unconscionable.

    • John Maurer (History)

      Actually, the potential strategic vulnerability of the US bomber force was a cause of great anxiety in the late 1950s/early 1960s. The development of intercontinental-range missiles led to fears that bombers would be wiped out on the ground. The Soviet attempt to position shorter-range, shorter-flight-time missiles in Cuba only further enhanced this anxiety.

      Check out Bernard Brodie’s “Strategy in the Missile Age” and Herman Kahn’s “On Thermonuclear War” for some thoughts on the vulnerability of the “bomber monad.”

    • JO (History)

      Strategy behind the idea is redundancy of critical assets. IMO, legitimate strategic thought has become boxed into a notion connected with particular delivery systems and even particular numbers, a bad direction. Tunnel vision limiting military debate has regularly created nasty surprises.

      The underlying redundancy is necessary. For instance, I personally would be worried if the US moved to an all-submarine nuclear force. Submarines rely on obscurity, and technology can remove obscurity.

      Thought experiment: the US active nuclear strike force is pared down to 12 patrolling SSBNs. An aggressor develops technology that reliably detects and tracks all twelve. How worthwhile is the nuclear deterrent?

      ICBMs rely on hardening rather than obscurity. Air delivery weapons can be dispersed widely and quickly. The genuine triad: concealment/hardening/dispersal.

  4. Jonah Speaks (History)

    If saving money is the main concern, getting rid of the submarine leg of the nuclear triad would save about two thirds of the cost of nuclear delivery systems. Under the sequester, the Navy gets to choose between the goal of a 300-ship navy or continuing the underwater leg of the nuclear triad, but not both. Because of its greater cost, maintenance of the submarine leg requires more justification than the other two legs.

    • John Schilling (History)

      Alternately, per Johnboy and the Israeli Navy, the submarine leg of the triad could be maintained by redeploying nuclear cruise missiles on SSNs/SSGNs. We are going to be maintaining nuclear submarines and submarine-launched cruise missiles for a long time to come, so the marginal cost of this alternative may be quite small.

      And as it turns out, we’ve already seen what happens when the Navy decides it doesn’t need as many SLBM tubes as it thought, and the answer isn’t scrapped SSBNs. It is rather Ohio-class SSGNs or special-operations support boats.

      So this isn’t, on the naval side, a simple “Triad, yea or nay?” argument, but a more general argument on what to do with the large, stealthy hulls we have already paid for and will probably maintain for their various useful capabilities. The answer isn’t obvious, and it is all too easy to fudge the analysis by assigning to favored missions only their marginal costs while offloading the fixed costs of the Ohio fleet on someone else’s mission.

    • j_kies (History)


      I thought this blog is about policy and philosophy of controlling arms, a mere cost argument seems dubious. Currently the Boomers/SLBMs have an unmatched safety and reliability record where the system is as credible a deterrent as you might wish. As a mobile launch platform the system is hidden and able to position itself for deterrence purposes flexibly. The recapitalization of the boomers is being executed as responsibly as any program within DOD. The personnel costs of the submarine crew training is spread within and enhances the overall USN submarine community.

      If we wish to examine the Triad – the system largely neglected in the last 30 years (the 1980s refit of the 1960s missiles) is now up for discussion. Other than having to overfly Canada and Russia to get anywhere and requiring staffing and training unique and unpopular specialties in the USAF, would someone please explain the real logic of recapitalizing land based strategic missiles? I suspect that new missiles especially if mobile will rapidly attain sustainment costs approaching or exceeding the Boomer based SLBMs.

    • George William Herbert (History)

      John, in light of Ohio replacement, new build class design and hull costs seem to drive us away from more big hulls unless we need large fleet SLBM boats. That the hull-starved conventional sub force jumped at the chance to grab four Ohios for essentially free does not mean they can make that a justified future force structure.

      That is probably why the Virginia stretch with four 89″ VLS tubes (enough for ten Tomhawk subtubes each) is programmed. But that’s not a new hull.

    • Jonah Speaks (History)

      Re: switching from SLBMs to SLCMs to save money. I thought we gave up the sea-launched cruise missiles to avoid presumed strategic dangers. If SLCMs can fly under radar, they created Soviet/Russian fears of a first-strike decapitating attack. Has anything changed in the past 20+ years to reduce the danger of SLCMs?

      Re: arms control and saving money. Personally, I see money savings as a lesser concern relative to nuclear dangers. However, we live in a world where different people view things in many different ways. Some people see budgets and cost savings as really important, and are oblivious to nuclear dangers. Sometimes, arms control can get more traction when it combines with cost savings.

    • John Schilling (History)

      I think cost is going to be central to any discussion of arms control among the great powers. The fear that a superpower nuclear spasm is likely to destroy civilization seems to have mostly faded. The concern that we are expending unreasonable ammounts of wealth on systems of dubious utility, has not. Any great-power arms control measures that are actually adopted, seem far more likely to be motivated by cost reduction than by risk reduction. And people who are genuinely concerned with risk reduction, ought to learn how to make cost arguments as well. How do we reduce the waste of economic resources that could be better used elsewhere, without inadvertently increasing risk due to asymmetries during the drawdown?

    • John Schilling (History)

      W/re submarines: The existence of Virginia Stretch, and the fact that Virginia was second choice to Seawolf, shows that the United States Navy at least has an (IMO well-founded) desire for hulls larger than any classic SSN and loaded up with assorted land-attack and littoral-warfare ordnance rather than just torpedoes.

      In the short term, this means that we’re going to be keeping all the Ohio hulls around for as long as we reasonably can. The question will be, what mix of Tridents, Tomahawks, SEALs, and Clever New Stuff is appropriate? I increasingly suspect that a force of 78% pure nuclear Tridents is suboptimal.

      Going forward, it means that we will be building boats bigger than an old 688 or even a Block I Virginia. The question then will be whether we need any or all of these boats to have full-size Trident tubes or can we get by with just a Tomahawk-scaled VLS, and either way what mix of actual capabilities we should put in the tubes. It may well be that retiring SLBMs altogether when the Ohios run out their service lives, and using nuclear cruise missiles for the maritime leg of the triad, is the best plan for a world where nuclear warfare is increasingly unlikely but can’t be taken completely off the table.

      Regarding the danger of SLCMs: we’re stuck with that. Submarines are inherently stealthy, and promises that we will never put nuclear warheads on SLCMs are not credible. Plus, it’s not just us; at least half a dozen powers now operate submarines with potentially nuclear-capable SLCMs, and they don’t fly flags.

      If anyone sees a missile pop out of the ocean and head in their general direction, they are going to worry that it is nuclear-tipped and aimed at decapitation. If anyone doesn’t see a missile pop out of the ocean and head in their general direction, they are going to worry that they weren’t looking hard enough and missed something. So long as submarines and cruise missiles exist, that danger will persist.

    • Jonah Speaks (History)

      Re: Stuck with nuclear SLCMs? “Submarines are inherently stealthy, and promises that we will never put nuclear warheads on SLCMs are not credible.”

      Are you claiming that a treaty which banned all nuclear weapons on ships and submarines would be inherently unverifiable? I can see the difficulty of verification when submarines are hiding in the ocean, but what about inspections of submarines while in port?

    • John Schilling (History)

      “Are you claiming that a treaty which banned all nuclear weapons on ships and submarines would be inherently unverifiable?”

      First, I think such a treaty is highly unlikely for the forseeable future. Essentially all of the nuclear powers see either SLBMs or SLCMs as a valuable part of their deterrent force. Some more so than others, and possibly open to persuasion, but getting unanimous buy-in from all the nuclear powers seems implausible.

      Second, yes, I think it is unverifiable. The idea for in-port inspections goes against the secrecy that is inherent in submarine operations generally. Inspecting a boat every time it leaves port means knowing the port schedule, and the inspectors can’t not notice that e.g. this time the boat is carrying a full load of commandos. You really think you are going to get the Israelis to sign up for an outside inspection every time a Dolphin leaves port?

      And if you did, there would still be the problem that the weapons loadout can be changed after the submarine leaves port. Submarine tenders are good at that. And submarine tenders can be camoflaged as merchantmen, so you don’t get to assume they will all be inspected.

      If a USN submarine launches a conventional Tomahawk at an Al Qaeda camp in Afghanistan, but the world situation is such that an Israeli nuclear sneak attack on Iran is plausible, I do not believe there is any technical or diplomatic means to plausibly assure people that the bird isn’t a Popeye Turbo carrying a hundred kilotons to Tehran. Or it could be a Pakistani attack on India, or the Chinese playing “let’s you and him fight”. Only way to know is to wait and see. Fortunately, this has proven adequate so far, but I understand the cause for concern.

    • Jonah Speaks (History)

      Re: Verifiability of treaty banning nuclear weapons on ships and submarines.

      I would agree that no treaty banning or significantly reducing nuclear weapons is likely in the near future. The U.S. and Russia are negotiating in slow motion and no other nuclear-armed country seems interested. So I discuss only feasibility, assuming political will can be generated someday.

      A submarine tender is a type of ship that supplies and supports submarines. Obviously, submarine tenders would need to be declared under the hypothetical treaty to ensure their inspection for nuclear weapons. If such ships were camouflaged as merchant ships and used to convey nuclear weapons, this would be a clear violation of such a treaty.

      Chronic peacetime violation of the treaty would eventually be discovered, through spies or tipsters, probably within a few years, if not sooner. One could speed this process of discovery by random inspection of ships and submarines outside ports.

      This leaves a one-off episode of cheating for purposes of a surprise attack. While it might be possible to sneak a few warheads on board ships or submarines, can one sneak on board a militarily significant quantity? In the U.S.-Russian context, I would define militarily significant as being enough warheads to demolish the opponent’s command and control in a surprise attack. The needed number is probably somewhere between 50 and 300 warheads.

      Because of fears of nuclear terrorism, there is a significant (unmet) desire to inspect all cargo ships for nuclear weapons. If a practical and economical method for quickly finding nuclear weapons on board cargo ships can be developed, even the loophole that merchant ships might convey nuclear weapons to submarines would be closed.

  5. Thomas (History)

    Costs are one thing, inter-service and parochial politics are another. As Mr. Krepon points out, the services generally want things of greater military utility. In terms of bombers, the Air Force is really more concerned with their conventional, rather than nuclear missions. Given the age of the current fleet, this means they want new bombers whether or not nuclear-capable cruise missiles or gravity bombs are still in the inventory. In the nuclear role, they are less vulnerable than ICBMs since they can be dispersed to bases around the country. Using B-2s, B-52s, and any future bomber in a conventional-only role probably doesn’t close any bases either unless you reduce the overall number of bombers.

    SSBNs, as pointed out by another poster, are the most expensive leg to build and maintain. Building the Ohio-replacement boats would take a huge bite from navy shipbuilding. Like bombers, the vehicle is only part of the story, you need missiles to fill the tubes too. Like bombers though, subs can be moved around, meaning they are harder to kill and their missiles would not have to over fly anyone, presuming an opponent has a coastline. SSBNs can be used in the conventional role to launch cruise missile or deploy SOF forces, but attack boats could do that either role more cheaply. Plus, I think submariners could be mollified if eliminating SSBNs meant more attack boats. If the SSBN fleet were eliminated or pared back, Kings Bay sub base in southern Georgia would probably face the ax. I think SSBNs are the most politically vulnerable leg of the Triad, though I think the Navy would fight to maintain a nuclear role even if it meant getting less SSBNs or other ships.

    My pick for elimination has always been the ICBMs due to their limited utility in a non-nuclear role, vulnerability, and the lack of a strong service attachment to them. ICBMs, while the least useful leg of the Triad, would probably be the most politically-difficult leg to eliminate. They are really only good for firing warheads at Russia, because they would have to overfly Russia in order to hit a target in the Northern Hemisphere. Any launch would look like an attack on Russia and an ICBM launch looks the same regardless of its payload. They are also the most vulnerable leg of the Triad since they are fixed in silos. Within the Air Force, only missile jocks are really attached to them as I understand it. On the Hill it’s another matter since three bases located in five states host them. Minot AFB (N. Dakota) has bombers too, but Warren AFB (headquartered in Wyoming, but with missiles in Nebraska and Colorado) and Malmstrom (Montana) have only ICBMs. In terms of cost, they are cheaper than subs, though the greater potential utility of SSBNs would help offset differences in cost.

  6. Bradley Laing (History)

    —One of my favorie authors wrote that the British Tornado fighter plane cost 112 times more than it’s WW II counterpart. “And since no country is 113 times richer than it was in 1945, militaries have grown small again.”

    —I know governments borrow money, have budget deficits, have national debts, and so on. But what measuring device can we use to show which countries have the “fill in the blanks” needed to make and maintain a certain size of nuclear delivery systems?

    —The point about the word “blanks” is to include the different types of measuring sticks. Tax revenue might not be the only thing needed.

  7. Bradley Laing (History)

    Correction: the number should be 113 in both sentances.

  8. Fred Miller (History)

    Star Wars fans get to talk about strategy without concern for their economic consequences. The rest of us don’t have that luxury.

    Strategic necessity is frequently discarded in favor of political convenience. How else explain the numerous B-52 bases in southern states? Or the persistence of antique B-52s in service at all?

    The KC-135 is being replaced by the KC-46, not because the KC-135s are ancient (45-55 years), but because Boeing, it’s union and it’s contractors lobbied hard and spent lavishly. To them, the tanker is not a strategic necessity. It is billions in corporate profits and billions more in wages, all of it adding to the national debt.

    Strategy matters, but economic and political concerns, sometimes of a very local nature, can trump even the most vital military necessity.

  9. Cthippo (History)

    I would argue that the manned bomber leg of the triad is most vulnerable simply because there aren’t going to be enough airframes to make it viable in another 20 years. Already “tactical” aircraft have demonstrated that they can take on most of the “strategic” roles, and while the Air Force might want a new manned bomber, I just don’t see it happening.

    Just as an Ohio replacement would largely prevent the Navy from building much of anything else, so would a new manned bomber compromise the tanker and F-35 programs which the Air Force has already committed to.

    Conversely, the ICBM force is probably the most secure because it wouldn’t need a new platform. New missiles could easily be made to fit in the existing holes in the ground. ICBMs are also the most accurate platform from a counter-force perspective, and probably have enough survivability for a second strike mission.

    How’s this for an idea for the next treaty with Moscow: A convention banning the construction or deployment of SSBNs. The Ohios are getting long in the tooth, we can’t afford their replacement, the Russian SSBN program is something of an expensive disaster and they’re already shifting their emphasis to ICBMs, and it would reduce the likelihood of a surprise attach.

    • j_kies (History)

      While the Ohio Replacement Program consumes a non-trivial chunk of future year ship-building planned scope, the advocates for grabbing that funding are surface navy partisans who gave us ‘gifts’ like the LCS. (which should discredit their claims of wisdom) Re-creating a SLCM program for all appropriate efforts including modern nuclear surety means is an effort rapidly approaching the development & T&E costs of the Ohio Replacement & D5.

      The options for changing the Triad are not fungable between elements. I am pretty certain that the recapitalization of the ICBM force wasn’t built into any FYDP or beyond planning. Further the costs of the ICBM force have to include the entire staffing chain and the regular O&M as well as the nuclear surety T&E with the development. Given the USAF avoided recapitalization for the last 30 years after SICBM cancellation again indicates that they quietly decided to let it wither some number of years back.

      After the Strategic Air Command went the way of the Dodo, a fairly good case could be made that we have a strategic MONAD today, its the boomers on patrol. Given the alert posture of the Bombers and the antique ICBMs with less than representative tests – any ‘deterrence’ value either provide above the Boomers is extemely nebulous.

      So the question today is ‘should the ICBM force be recapitalized and why’ further what other future program should the USAF sacrifice to pay for it?

  10. archjr (History)

    We have x number of nuclear weapons. http://abcnews.go.com/blogs/politics/2013/06/how-many-nuclear-weapons-does-the-us-have-dont-ask-a-congressman/

    I for one would like to see an analysis done of what we can’t accomplish with a thousand, or five hundred, or three hundred nuclear weapons (or zero, but come on). In a parallel, arms-control-nirvana universe, we would give them a number and let the “joint” services fight it out. In the meantime, let’s see some budget justifications for maintaining any single portion of the triad in the context of whatever NPR we have in front of us (and for me, they have seemed nonsensical for a long time).

    DOD should be forced to defend the triad as a concept, being that the world has changed a good bit.