Comments on “The New Era of Nuclear Arsenal Vulnerability” by Lieber and Press, Physics & Society, January 2018

Frank von Hippel1*, 30 December 2017

“In the Cold War, we always thought that the danger was that the Soviet Union was going to conduct a surprise attack as a bolt out of the blue; and all of our policies, all of our weapons programs, and so on were based on responding to that. But that was never the threat. The threat was always that we would blunder into a nuclear war, and that threat was almost realized in the Cuban missile crisis.”
– William Perry, former Secretary of Defense, Arms Control Today, December 2017, p. 43.

Lieber and Press’ article is the latest in a long series that started in 2006 with “The end of MAD” in International Security, which was summarized in Foreign Affairs under the title, “The Rise of U.S. Nuclear Primacy”. In that second article, the authors declared “Russia's leaders can no longer count on a survivable nuclear deterrent [and] China's nuclear arsenal is even more vulnerable to a U.S. attack.”

This argument for the credibility of a bolt-out-of-the-blue U.S. nuclear first strike on non-alert Chinese or Russian nuclear forces, with millions of fatalities inevitably resulting, was shocking and resulted in a number of rebuttals – perhaps most thoroughly in an article by Bruce Blair and Yali Chen in China Security, a journal aimed at a Chinese as well as American audience.1

A decade later, in Physics and Society, Lieber and Press talk more cautiously about a trend toward vulnerability for Russia and China – perhaps because both countries are modernizing their nuclear forces and Russia is deploying a larger share of its ballistic missile submarines at sea and mobile land-based missiles in the field, making them less vulnerable.

In the jargon of nuclear-weapons policy analysts, what is being discussed are “counterforce” techniques for attacking an adversary’s nuclear missiles and bombers before they can be launched. Arms controllers have for 50 years warned about the dangers of the U.S. military’s pursuit of counterforce capabilities against Russian and Chinese nuclear weapons. George Rathjens wrote an excellent article on the subject in Scientific American in 1969, “The Dynamics of the Arms Race.” When the Reagan Administration proposed adding 10,000 accurate counterforce warheads on U.S. ballistic and cruise missiles in the early 1980s, it caused so much alarm that a grass-roots movement to “freeze” the nuclear arms race rose in response and helped end the Cold War.2

Lieber and Press’ efforts to publicize the vulnerability of Russia’s and China’s nuclear forces to a U.S. bolt-out-of-the-blue attack makes arms controllers nervous because such assertions feed the paranoia of worst-case analysts in those countries and increases the danger of accidental nuclear war.

In his book, The Doomsday Machine, Daniel Ellsberg recounts how, in the midst of the 1961 crisis over U.S. access to West Berlin, the Kennedy Administration communicated to the Soviet Union that new U.S. photographic satellites had discovered that the U.S. was way ahead of the Soviet Union in deploying intercontinental nuclear ballistic – an obvious counterforce threat.3 This drove Khrushchev to the desperate stratagem of secretly sending medium and intermediate-range ballistic missiles to Cuba within range of the United States, triggering an extraordinarily serious nuclear crisis.

Counterforce drives a number of dangerous dynamics. One is that it is used to justify large nuclear forces. As we are learning again with North Korea, it would take only a few warheads to gravely wound a large nuclear-weapon state but many to target its nuclear missiles, the airports to which it might disperse its nuclear-armed bombers, its command centers and communications systems and its nuclear-weapon production and storage sites.

The demands for more warheads made in the name of counterforce during the Cold War led to even larger target lists. The U.S. nuclear target list for 1959 contained a total of 4609 Designated Ground Zeros (DGZs) for nuclear weapons including 178 in Moscow. Of the targets in Moscow, 3 were military and command headquarters, 8 related to radio and television transmission, 10 were military storage areas, 14 related to the electrical grid, 16 were aircraft body and engine factories, 18 related to liquid fuel storage and production, 33 were railroad yards and shops, and the remaining 90 ranged from factories producing agricultural equipment to antibiotics. There were similarly 145 DGZs for Leningrad, 68 in East Berlin, 39 in Warsaw and 18 in Beijing. In each of these cities, there was even one DGZ labeled simply “population”.4 In 1961, Ellsberg contrived to get the new Kennedy White House to ask the Strategic Air Command how many people its Single Integrated Operations Plan would kill. To his surprise, they had an estimate, 600 million – or, as Ellsberg describes it, “100 Holocausts.”5

A second perverse and dangerous consequence of nuclear counterforce is that it provides an incentive to launch on warning before the counterforce attack arrives. Although the commanders of U.S. strategic nuclear forces deny that this is a “hair-trigger posture,” it is. The U.S. and Russian early warning systems have given false warnings of incoming attacks many times. Publicly-known cases on the U.S. side include a technician playing a training tape without informing the staff of the U.S. early-warning center and a faulty computer chip.6 On the Soviet side, in 1983, the early-warning system misinterpreted the reflection of sunlight off the top of clouds as plumes from U.S. intercontinental missiles rising from their silos in the Great Plains7 and, in 1995, a scientific rocket launched from an island off Norway was mistaken for a Trident II nuclear missile launched from a U.S. ballistic-missile submarine.8

Because the flight time of a ballistic missile from Russia to the U.S. is about 30 minutes and the flight time from the North Atlantic off Norway to Moscow is about 10 minutes, any decision on launch on warning must be made in a matter of minutes. Since we are still here, it appears that to date all false nuclear alarms have either been identified as such within this period or decisions were made to ignore them. But can we expect our luck to hold indefinitely?

Thus, Lieber and Press have spot-lighted a serious concern for any U.S. adversary with nuclear weapons: the possibility that a U.S. President might opt for in a surprise attack to try to knock out its nuclear deterrent. At a time of worsening tensions with Russia, the idea that a bolt-out-of-the blue attack by the U.S. on Russia’s nuclear forces is thinkable could make false alarms from Russia’s inadequate early warning system more credible and increase the probability of Russia’s hair trigger going off. China does not yet have an early warning system and has therefore not been in a position to adopt a launch-on-warning posture. But it is concerned about the possibility of a U.S. first strikes and this concern is being exacerbated by the U.S. drive to build a ballistic missile defense – nominally against North Korea. Perhaps in response, China has been building up the number of its missiles that can reach the United States, making the already difficult two-body problem of negotiating further reductions with Russia into a much more difficult three-body problem.

In the view of many arms-controllers, the United States and the world would be safer if we changed our policy to no first use, abandoned the options of launch on warning and nuclear preemption, and decided that no single person will have the unfettered power to launch U.S. nuclear weapons.

President Obama’s failure to institute any of these changes demonstrates, however, that they will not happen in the absence of a powerful public movement. North Korea’s increasingly credible nuclear threats and the Trump Administration’s threats of preventative nuclear war may, for the first time since the 1980s, have created the conditions for such a movement.

In the past, American physicists have played an important role in educating their fellow citizens about the dangers from nuclear weapons and how those dangers might be reduced. I have written this in the hope that some members of the next generations of physicists will read it and carry on this noble tradition.

* Frank N. von Hippel is a senior research scientist and Professor of Public and International Affairs emeritus at Princeton University’s Program on Science and Global Security. During 1993-4, he served as Assistant Director for National Security in the White House Office of Science and Technology Policy. He was awarded the Forum on Physics and Society’s Leo Szilard Lectureship in 2010.

1 Bruce G. Blair and Chen Yali, “The Fallacy of Nuclear Primacy,” China Security, Autumn 2006, pp. 51–77,

2 Matthew Evangelista, Unarmed Forces: The Trans-national Movement to End the Cold War (Cornell University Press, 1999).

3 Daniel Ellsberg, The Doomsday Machine: Confessions of a Nuclear War Planner (Bloomsbury Press, 2017) chapter 10.

4 “U.S. Cold War Nuclear Target Lists Declassified for First Time,” As of this writing, this was the only declassified target list.

5 The Doomsday Machine, Prologue.

6 Recent False Alerts from the Nation’s Missile Attack Warning System, U.S. Senate Committee on Armed Services, 1980.

7 Colin Freeman, “How did one grumpy Russian halt Armageddon?” The Telegraph, 11 May 2015,

8 Geoffrey Forden, Pavel Podvig and Theodore Postol, “False alarm, nuclear danger,” IEEE Spectrum, March 2000, pp. 31-39.

These contributions have not been peer-refereed. They represent solely the view(s) of the author(s) and not necessarily the view of APS.