The terrorist attacks on New York and Washington on September 11, 2001, were both good and bad news for the Bush Administration's early commitment to the near-term deployment of defenses against ballistic missiles. The good news was that the vulnerability of the American homeland to devastating attack was demonstrated to be real, not merely a figment of the overactive imagination of Reagan-era strategists. The bad news, on the other hand, was that the method of attack utilized by the terrorists involved neither ballistic missiles nor nuclear weapons. Al-Qaeda's largely unanticipated concept--the use of fuel-laden commercial airliners in suicide missions to produce enhanced conventional explosive effects--inflicted less damage than might be anticipated from most so-called weapons of mass destruction, but it was well suited to a technically constrained and low-budget terrorist organization.
Critics of ballistic missile defense (BMD) were quick to seize on 9/11 as proof that the real threats of the future were likely to come not from intercontinental-range missiles with a recognizable "return address", but rather from a variety of possible weapons or devices clandestinely inserted into the United States, or even from aircraft or cruise missiles originating within the country or not far from its borders. They argued that states capable of attacking the United States with long-range ballistic missiles will continue to be deterred from such a step by America's overwhelming retaliatory capabilities. And missile defense is technically problematic and enormously expensive compared to other pressing defense needs.
