Thomas Kuhn, in his seminal work The Structure of Scientific Revolutions, explains how large areas of science evolve from one organizing concept or “paradigm” to a new one when the old model can no longer account for much of what scientists observe. Thus, Copernicus and the centrality of the sun in our solar system transformed astronomy, just as Darwin’s theory of natural selection and its relevance for evolution fundamentally altered the study of biology.
We may be approaching such a threshold in the realm of social science. For half a century, nuclear war has been avoided thanks to deterrence and the notion that striking first held out little attraction because the other party could and would retaliate with devastating consequences. This concept was codified in the 1972 Anti-Ballistic Missile Treaty (ABM) Treaty, in which the United States and the Soviet Union agreed to keep to an absolute minimum their capacity to shoot down the ballistic missiles of the other side.
Subsequent arms-control agreements—the SALT and START pacts alike—were negotiated and implemented in this context. Levels and types of nuclear weapons were simultaneously permitted and limited so as not to challenge the fundamental reality of mutual vulnerability.
The question now is whether the time is ripe to make the transition to another strategic paradigm, one in which the levels of offensive and defensive systems change in both absolute and relative terms. More specifically, the question before us is whether it makes sense to move to a world of less nuclear offense and more missile defense.
This question results from several changes. The first is the end of the Cold War. It no longer makes sense (leaving aside the issue if it ever did) for the United States and Russia to maintain massive nuclear arsenals capable of destroying one another many times over. The two countries may not be allies, but neither are they adversaries engaged in a global struggle and bent on the other’s destruction. Moreover, maintaining large inventories of missiles is dangerous—the chance of accidental or unauthorized launches can never be eliminated—and expensive.
Second, new threats are appearing, and more may follow. In particular, a number of countries, including but not limited to North Korea, Iraq and Iran, are developing ballistic missiles and possibly nuclear weapons to go with them. Depending on their range, these missiles could threaten U.S. troops in critical regions, American allies or U.S. territory. Leaders of these countries may not be deterred by the same logic that worked vis-à-vis the Soviet Union.
The third development involves the emergence (and promise) of new technologies that make the prospect of intercepting ballistic missiles at one or another stage of their flight—hitting a bullet with a bullet—more real than ever before.
This logic appears to have persuaded presidential hopeful George W. Bush to support moving to a new strategic paradigm. Speaking in Washington May 23, Bush committed himself to a nuclear-weapons arsenal reduced to “the lowest possible number consistent with our national security.” He advocated a defense designed “to protect all 50 states and our friends and allies and deployed forces overseas from missile attacks by rogue nations or accidental launches.”
Such new thinking is not universal. Critics contend that more defense will prompt Russia to refuse to reduce nuclear weapons and China to build more. Critics also claim that missile defense will not work against incoming warheads surrounded by decoys, that it will be terribly expensive and that the threat of rogue-state proliferation can be better addressed through prevention (using diplomacy and export controls) and deterrence.
The Clinton administration has sought to split the difference by advocating a policy of somewhat smaller arsenals coupled with somewhat more defense. More specifically, it favors trying to persuade Russia to agree to amend the 1972 ABM Treaty to allow each side to build a sharply limited national missile defense with 100 interceptor missiles located in Alaska and possibly 150 more at a second site.
This attempt to introduce modest changes within the existing strategic paradigm has won few converts. Clinton’s brand of limited missile defense appears to be too much for the Russians, who fear it is the start of something much larger that would threaten their strategic position. And it is too little for Republican advocates of missile defense, who fear being locked into a new framework that will be overly confining.
Given these realities, President Clinton would be wise to defer any decision on missile defense in the final months of his presidency. Too little is known about various options to commit ourselves to one and reject others. First, the United States should do three things: aggressive testing of various architectures, including sea-based systems that could intercept missiles in the immediate post-launch, boost phase before warheads and decoys were released; careful study of the consequences of moving to various mixes of offensive and defensive systems; and intense consultations with Russia, China and America’s allies in Europe and Asia about how best to maintain strategic stability in the post-Cold War era.
Paradigm shifts are by definition major undertakings. Americans never would alter the way we fund an entitlement program or administer education without serious study and widespread debate. Maintaining stability in what remains a nuclear age would seem to warrant no less responsible an approach.