Secretary of State Hillary Clinton said recently in Thailand that if Iran acquires a nuclear weapon, the U.S. will offer allies in the Middle East a "defense umbrella" to prevent Iranian intimidation. That's a fine sentiment, but it raises the question: Are we capable of doing so?
The answer is more complicated than most people think.
The proliferation of weapons of mass destruction and associated delivery systems since the collapse of the Soviet Union means that any "defense umbrella" will require the deployment of missile defense technologies capable of neutralizing a potential salvo of nuclear-tipped missiles—whether from Iran or another rogue such as North Korea.
Yet America's missile-defense efforts are being scaled back. Congress is contemplating a $1.4 billion reduction to the Pentagon's budget for antimissile capabilities.
Advocates of missile defense are seriously concerned that this is just the beginning, and that the Obama administration seeks to kill the system with a thousand cuts. During the presidential campaign last year, Barack Obama promised to strip $10 billion from the Pentagon's budget for missile defense. (Actually, the U.S. currently spends only $9 billion in this area.)
The Bush administration began work on a linked network of individual missile-defense systems capable of intercepting ballistic missiles in all stages of flight. But it built only the capabilities necessary to counter simple rogue-state threats, such as a single missile launched from North Korea and aimed at the West Coast. The administration's efforts stopped short of a comprehensive architecture that would include antimissile systems on land, on the seas, and in space.
The Obama administration wants to scale back from Bush's modest beginnings. In addition to slashing the overall budget for missile defense, it has terminated promising projects such as the multiple-kill vehicle (MKV) program—in which multiple interceptors on a carrier vehicle (essentially a satellite) would improve our chances of hitting enemy missiles. Another project terminated is the airborne laser (ABL), an aircraft-based high energy laser that could be flown near potential enemy ballistic-missile hotspots.
Mr. Obama has also targeted the Bush administration's premier missile-defense venture, the deployment of ground-based interceptors and radars in Poland and the Czech Republic to defend against the growing ballistic missile threat from Iran. Instead, because of the Kremlin's objections, the Obama team is preparing to sacrifice this planned deployment as part of a "reset" of U.S. relations with Russia.
Space-based missile defense likewise has been met with a cold shoulder from the Obama administration. Opponents of missile defense charge that a space layer would somehow "militarize" space. This is dead wrong. A space-based missile defense capability would instead block and destroy weapons that enter the Earth's orbit on their way to their targets.
The most promising idea would be to develop a program for the deployment of space-based kinetic interceptors capable of targeting intercontinental ballistic missiles in their boost, midcourse and terminal phases of flight. In other words, let's revive the useful idea of building a system that gives us multiple chances to knock out every enemy missile.
Sadly, in the current political atmosphere, missile defense has become an ideological football. Republicans and Democrats alike ought to be united in the effort to develop a serious system capable of protecting the American people, our armed forces and our allies abroad from ballistic missile attack. A half-hearted missile defense effort only encourages investments in missile technologies on the part of our adversaries, making them believe that with additional resources they will be capable of overwhelming American defenses.
U.S. missile-defense policy should be designed to elicit the opposite response. Our enemies and competitors should be forced to conclude that energy and funds spent developing nuclear weapons and the missiles to deliver them will be wasted because Americans have the know-how and hardware to prevent them from reaching their intended targets.
During the Ronald Reagan and George H.W. Bush administrations, the U.S. government made major investments in the types of technologies (space-based sensors, interceptors and propulsion) necessary to field a robust defense against foreign ballistic missile arsenals, irrespective of origin. The capability to make Iranian, North Korean and other foreign missiles useless has already been developed and field-tested. Only America has it, and we should deploy it.
Mrs. Clinton has the right idea. The U.S. should offer a comprehensive and impenetrable "defense umbrella" to protect itself and its allies. But first we need to match rhetoric with concrete action and get the job done.
Mr. Berman is vice president for policy of the American Foreign Policy Council. Mr. May is the president of the Foundation for Defense of Democracies.