On December 13, 2001, President Bush announced that in six months the United States would withdraw from the 1972 ABM treaty, a treaty that limits the testing and prohibits the deployment of any national missile defense system by Russia or the US. The stated reason for this decision was that the United States needs to develop a system that would protect us from attack by intercontinental ballistic missiles launched by terrorists or by a so-called rogue state. The US has not yet withdrawn from the treaty; this is the formal six months’ advance notice that is required by the treaty, and the President could still decide not to withdraw, but it is hard to imagine that anything could happen before June 2002 that would change his mind.
The arguments by scientists and members of Congress that the US could continue an active program of developing and testing missile defense systems without abrogating the ABM treaty now seem moot. But the issue of whether to actually develop and deploy a national missile defense system is not moot, and will not be settled even after the treaty is abrogated. Requests for missile defense funding will come up again in Congress in mid-2002, and in subsequent years. We can anticipate a continuing national debate about whether the US should seek to develop and deploy a national system of defense against intercontinental ballistic missiles.
Few of the arguments in this debate will be new. Indeed, it is hard to remember a time when the US has not been arguing about a national missile defense program. Almost half a century ago, in the Eisenhower administration, the Army proposed to convert the old Nike antiaircraft system to an antimissile system called Nike Zeus, which would send radar-guided nuclear- armed rockets to intercept Soviet warheads as they plunged through the atmosphere toward US cities. It had obvious failings: the nuclear blasts from successful interceptions could put our radars out of action, and the stock of interceptor missiles could be exhausted if the enemy missiles carried several light decoys along with each warhead.
In the Kennedy administration the Nike Zeus plan was upgraded to a two-tier project called Nike X. Long-range nuclear-armed missiles called Spartans would attempt to intercept Soviet missiles while they were still coasting above the earth’s atmosphere; short-range Sprint missiles would then deal in the atmosphere with those warheads that had survived the Spartan attack. As a member of the JASON group of defense consultants, I worked in the 1960s on the problem of discriminating decoys from warheads, and learned how difficult it is. Like others before me, I gradually also became influenced by a powerful argument against deploying any missile defense system: that in the conditions of the times it would simply induce the Soviets to increase their offensive intercontinental missile forces, leaving us worse off than before.
Despite such arguments, the Johnson administration came under powerful political pressure to go ahead with some sort of missile defense. In 1967 Defense …