U.S. security interests also dictate that the United States consider Chinese reactions to its missile defense plans. Although not a party to the ABM Treaty, China bases its nuclear planning in part on the treaty and has historically been concerned about U.S. and Soviet missile defense programs. China is believed to have several hundred nuclear weapons but perhaps only about two dozen are able to reach the United States. Even a limited national missile defense system, therefore, could undermine or negate the Chinese deterrent.
China has expressed concern about high-altitude theater defenses too. Sha Zukang, China’s ambassador to the Conference on Disarmament, noted in a statement to the U.N. General Assembly last October that such systems will “possess the capability to intercept strategic missiles” and that their development thus would dampen China’s “enthusiasm to participate in the global process of arms control and disarmament.” Moreover, U.S. deployment of high-altitude theater defenses would open the door for Russia to do the same. Such a move could threaten the bulk of China’s missile force, which have ranges of less than 3,500 kilometers and constitute the backbone of its deterrent against Russia.
China also worries about possible transfers of U.S. theater defenses to neighboring countries and U.S. deployment of sea-based systems in the region. The United States has tried to enlist Japan as a partner to help fund development of THAAD. China views Japan as a latent nuclear power, and given the historical enmity between the two countries, is uncomfortable with the prospect of a potential combination of Japanese nuclear weapons and missile defenses. Japan has recently all but opted out of the THAAD project, however, partly because the cost is too high and partly to minimize tensions with China.
China is also upset by U.S. plans to sell Patriot defenses to Taiwan in response to the intimidating missile tests China conducted off Taiwan’s coast prior to Taiwan’s elections last year. Because these are only low-altitude defenses, however, such a sale is unlikely to affect China’s nuclear or arms-control policies.
Given its concerns, China could react to U.S. missile defenses in a number of ways that could reduce U.S. security and hinder further efforts to control and eliminate the world’s nuclear arsenals. To preserve its nuclear deterrent, China, like Russia, could build up its nuclear forces or adopt a launch-on-warning posture. China could also decide to keep open the option of building up by refusing constraints on fissile material production. The United States is seeking an international treaty prohibiting further production of fissile material for nuclear weapons, partly as a way to place some controls on the nuclear-weapon programs of the undeclared nuclear states-India, Israel, and Pakistan. China’s agreement to this treaty is essential, both because of its own nuclear arsenal and because its participation will be needed to gain that of India and, in turn, Pakistan.
If and when the United States and Russia continue to cut their deployed nuclear weapons to roughly the numbers held by the smaller nuclear powers-China, Britain, and France-it will become necessary to include these countries in negotiating deeper cuts. But in response to U.S. defenses, China could hamstring this process by refusing to accept limits on its deployed arsenal.
Finally, because both Russia and China are potential suppliers of nuclear and missile technologies to other countries, their participation in international nonproliferation efforts is crucial. But the ill will that missile defense deployments could cause may make both Russia and China less willing to cooperate with the West on restricting transfers of sensitive technology to other countries, or to participate in other nonproliferation initiatives.
Thus the overall result of U.S. deployment of national missile defenses and high-altitude theater defenses could well be that nuclear reductions and other irreversibility measures grind to a halt and that the United States and Russia become locked in at high levels of deployed weapons, while retaining their ability to rapidly build more. The other nuclear weapon states would then refuse to become involved in nuclear arms reductions. Creating such barriers to deep nuclear reductions and disarmament, which the nuclear weapon states are obligated to pursue under the Nuclear Non-Proliferation Treaty (NPT), would become increasingly unacceptable to the 180 non-nuclear-weapon state members of the NPT. Over time, this discontent could weaken the international nonproliferation regime.
These potential costs to U.S. security might be worth risking if the missile threat were greater and defenses were a more effective means of countering this threat. But this is not the case. There is no missile threat from developing countries that justifies national missile defenses, and there may never be. There are more effective means of addressing the problem of accidental and unauthorized launches from Russia and China. No long-range theater missiles justify deployment of high-altitude theater defenses; low-altitude defenses will provide most if not all of the realizable benefits of defenses against existing and likely future theater missiles, and without the attendant security costs.
The desire to defend the United States, its troops, and allies against all threats is understandable. But U.S. policymakers must weigh both the costs and benefits of deploying missile defenses. U.S. security-and indeed international security-will best be served if the United States forgoes national missile defenses and high-altitude theater defenses.n