President Bush has given formal notice to Russia that the United States will withdraw from the Anti-Ballistic Missile (ABM) Treaty in six months. The development of a limited national missile defense (NMD) to protect the U.S. homeland might eventually require withdrawal from the ABM Treaty, but now is not the time to make that decision.
First, the testing program for the most mature elements of even a limited land-based missile defense system is still in its infancy. An NMD is the most complex weapon system ever developed and the technology is unproven. Therefore, as with any other high-tech weapon system, a thorough test program is needed. The results of testing to date are largely positive and promising, but it is still too early to make a deployment decision, which would require either amending, renegotiating, or withdrawing from the treaty. Adequate testing of a limited land-based system can continue within the constraints of the treaty. Therefore, there is no immediately compelling reason to unilaterally withdraw from the treaty.
Second, President Bush claims that the ABM Treaty "hinders our government's ability to develop ways to protect our people from future terrorist or rogue-state missile attacks." But ballistic missiles are the least likely means by which terrorists would deliver a weapon against the United States. A missile provides an immediately known point of origin, which would likely result in immediate U.S. retaliation against the country of launch with the most powerful nuclear arsenal on the planet. In addition, terrorists would probably have greater difficulty developing, acquiring or using an intercontinental missile than they would nuclear, chemical or biological weapons delivered by easier and cheaper means. If a missile threat from a rogue state (for example, Iran, Iraq, or North Korea) emerges, it will not materialize for a number of years. Since both the threat and a thoroughly tested limited land-based missile defense system are still in the future, the United States does not now need to abandon the ABM Treaty and can continue testing until a well-informed deployment decision can be made.
Finally, although President Bush stated that Russian President Putin agreed that the "decision to withdraw from the treaty will not in any way undermine our new relationship or Russian security," withdrawing from the treaty (together with another round of NATO expansion) could unnecessarily antagonize the Russians and result in unintended outcomes as Russia responds with their own national security interests in mind. Thus, withdrawal from the ABM Treaty might potentially undermine the great progress made in the changing U.S.-Russian relationship, especially the agreement by both presidents to dramatically reduce strategic nuclear arsenals and the two nations' continued cooperation on the war on terrorism and safeguarding Russia's dangerous stockpile of weapons of mass destruction. In addition, the European allies and China are not thrilled with U.S. withdrawal from the treaty. The European allies are afraid of an adverse Russian reaction, and China is concerned that a U.S. NMD will neutralize its small nuclear deterrent.
In short, the timing of the administration's decision could not be worse. The United States will incur all of the negative international consequences of withdrawing from the treaty in the short-term, but the threat and the technology will only develop over the long-term (if ever).
Ultimately, it may be necessary and in America's national security interests to withdraw from the ABM Treaty. But continued development and testing of a limited land-based system to defend the U.S. homeland does not require withdrawal now. The only reason to withdraw from the ABM Treaty now is to pursue a more robust, global missile defense (including sea-based, air-based and space-based defenses) that is designed to protect friends and allies around the world -- all of whom are rich enough to pay for their own missile defenses. And such a robust and far-flung missile defense could actually encourage U.S. policymakers to engage in reckless overseas military adventures against nations with weapons of mass destruction and long-range missiles, which would undermine - not enhance - U.S. national security.
Even a limited land-based system, the closest to fruition, will probably not be fielded until the turn of the decade. Sea- and air-based technology will take longer, and pie-in-the-sky space-based defensive weapons are far in the future. Finally, such a comprehensive and grandiose missile defense would probably cost well over $100 billion, compared with the $30 to $60 billion required for a limited land-based system.
In sum, the United States can do all the research it needs to develop a limited land-based NMD system within the constraints of the ABM Treaty. It is premature to withdraw from the treaty until that technology is proved and the system is ready for deployment.