Jeffrey LewisRussia’s Nuclear Powered Cruise Missile

From the moment that Russia unveiled its nuclear-powered cruise missile, I was referring people to my neighbor up in Santa Cruz, Gregg Herken. (West Coast, Best Coast!)  Gregg is one our finest historians of the Cold War and he just happened to have written wonderful little account of Project Pluto, America’s own effort at such a crazy device, in a 1990 article for Air & Space Magazine entitled “The Flying Crowbar“.

So I was delighted that Gregg was willing to send along his thoughts on Putin’s new wonder weapons.

Putin’s “Invincible Missile”?  Meh. 

Gregg Herken

Earlier this month, Russian President Vladimir Putin announced development of a nuclear-powered, nuclear-armed cruise missile with virtually unlimited range.  Putin called it “a fundamentally new type of weapon”—an “invincible missile” able to evade American defenses.  Some military analysts promptly hyper-ventilated.   “If we’re talking about nuclear-armed cruise missiles, that’s a technological breakthrough and a gigantic achievement,” said one.  “[T]hese weapons are definitely new, absolutely new.”  Well, actually…no.  In fact, the United States developed a nuclear-powered cruise missile prototype in the early 1960s.  “Project Pluto” was part of a Pentagon program known as SLAM, for supersonic-low-altitude missile.  SLAM was cancelled in 1964, never having taken flight.  Nuclear-powered cruise missiles were not a good idea then, and they are not a good idea in Cold War 2.0.

Which is not to say that such weapons are not sexy, in a way.  SLAM envisioned a locomotive-sized missile flying at three times the speed of sound near tree-top level, tossing out hydrogen bombs along the way, and spewing radiation in its wake.  There was a reason why Pluto’s inventors, at the Livermore nuclear weapons laboratory in California, dubbed it “the weapon from Hell.”  The noise level on the ground when Pluto went by was expected to be 150 decibels.  (The Saturn V Moon rocket, by comparison, produced 200 decibels at full thrust.)  But ruptured eardrums would have been the least of your worries if you were in the neighborhood.   The shock wave alone might have been lethal.  And, since Pluto’s nuclear ramjet engine ran at 2,500 degrees Fahrenheit, portions of the missile would have been red-hot—literally ”frying chicken in the barnyard” on the way to its targets.   Indeed, SLAM operated on the same principle as the errant low-flying B-52 bomber in Dr. Strangelove.  As Col. Kong observed to his crew, “they might harpoon us, but they dang sure ain’t going to spot us on no radar screen.”  One Livermore engineer told me that SLAM would be flattening, burning, and irradiating the enemy even before it dropped the first bomb.

Which was, in part, the problem.  Where do you test a flying nuclear reactor?  (Russia’s version of Pluto reportedly used an “electric power source” to simulate the nuclear engine.)  Livermore physicists initially proposed that Pluto be flown in a figure-eight pattern over the remote Pacific, prompting one ask:  “How are you going to convince people that it is not going to get away and run at low level through Las Vegas—or even Los Angeles?”  An alternate idea was to tie Pluto to a tether at the Nevada Test Site.  (“That would have been some tether,” observed another scientist at the lab.)  Finally, what do you do with a highly-radioactive missile once it’s been tested?  Dumping it in the ocean was the solution proffered back then.  Ultimately, cooler heads prevailed.  Six weeks after the successful static test of Livermore’s nuclear engine in Nevada, the Pentagon pulled the plug on Pluto.  Intercontinental-range ballistic missiles (ICBMs) promised to destroy targets in the Soviet Union well before Pluto got to them, and with equal certainty.  SLAM, its critics said, stood for “slow, low, and messy.”

But Pluto, it seems, has risen again, this time in a Russian incarnation—a nuclear-powered Frankenstein, a flying Chernobyl.  Putin’s new cruise missile also has a sea-going sibling:  a giant nuclear-powered torpedo designed to destroy U.S. port cities with a multi-megaton blast.  This weapon, known thus far only as Status-6, bears a striking resemblance to the idea that Russia’s Nobel-Prize-winning physicist, Andrei Sakharov, came up with in the early 1960s.  When Sakharov told a Soviet admiral of his proposal, however, the latter was “shocked and disgusted by the idea of merciless mass slaughter.”  Feeling “utterly abashed,” the physicist abandoned the concept, and never raised it again.  “I’m no longer worried that someone may pick up on the idea,” Sakharov wrote in his Memoirs, published in 1990.  “[I]t doesn’t fit in with current military doctrines, and it would be foolish to spend the extravagant sums required…”

Plainly, times have changed.  Yet, as several experts have since noted, it is likely that Putin’s amazing new weapons are only part of a propaganda campaign, a response to plans recently announced by the Trump administration to expand and modernize America’s nuclear arsenal.  If so, Putin’s ploy is reminiscent of Soviet Premier Nikita Khrushchev’s hollow boast in the ‘Sixties that the USSR was turning out ICBMs “like sausages.”  (As Khrushchev’s son, Sergei, later observed, his father wasn’t exactly lying:  the Soviets weren’t making sausages then either.)

But the real danger of Putin’s announcement is that it will—as Khrushchev’s boast did then—spark an American over-reaction, and lead to pressure to revive ideas like Livermore’s Pluto and Sakharov’s torpedo:  forgotten relics of Cold War 1.0 that are best left dead and buried.

Gregg Herken is an emeritus professor of American diplomatic history at the University of California.  In 1988-2003, he was Curator of Military Space at the Smithsonian’s National Air & Space Museum.