Physics and National Security: Of Missiles, Mines, and Morality

Gronlund, Lewis, and Wright reply: We have not investigated the extent to which Russia might mistake a launch of national missile defense (NMD) interceptors for that of offensive US missiles, but this is not an idle concern: In 1995, a scientific research rocket fired from Norway was detected by Russia’s early warning system and triggered a false alarm that traveled all the way up the chain of command to President Boris Yeltsin. Moreover, as Allen Thomson notes, Russia’s early warning system is deteriorating.

But there is a more fundamental way in which the US deployment of an NMD system could increase the risk of Russia’s launching its nuclear armed missiles in response to a mistaken warning of an incoming US attack.

The US and Russia both maintain large numbers of nuclear-tipped missiles that can be launched within minutes. Such a launch-on-warning posture is risky at best, but Russia’s deteriorating warning system exacerbates the dangers. Because a mistaken attack from Russia is one of the greatest nuclear dangers to the US, our government should be doing everything in its power to encourage Russia to reduce its launch-on-warning capability. Yet, US deployment of a missile defense that Russia believes might be able to intercept a significant fraction of its survivable missiles will instead serve as an incentive for Russia to maintain this dangerous capability.

This linkage between US missile defenses and Russian launch-on-warning policy was demonstrated clearly in leaked US State Department documents used in the January 2000 US–Russia negotiations to modify the Anti-Ballistic Missile Treaty to permit deployment of the planned NMD system. ¹ State Department officials argued that the system would not threaten Russia’s deterrent as long as Russia continued to deploy 1000 or more nuclear warheads and maintained the ability to launch promptly on warning of a US attack.