Under Bush the budget for missile defense soared. The budget he inherited upon taking office in 2001 had $4.8 billion for missile defense. The next year it jumped to $7.8 billion; this year it is nearly $10 billion. Over the course of Bush's eight years as president the cumulative total likely will hit $70 billion. That compares with missile defense budgets totaling about $36 billion over the prior 10 years.
A central point of debate for decades has been whether missile defense would work. In a sense, it's not possible to know at this stage because it has never been used against a hostile long-range missile.
On the other hand, supporters point out that it has worked in real attacks by shorter-range missiles -- like in Iraq at the outset of the current war -- but never those aimed at US soil. Supporters also point to successful tests, while acknowledging that those simulate fairly simple attacks by single warheads rather than a possible real-world assault by multiple warheads using decoy methods.
The Union of Concerned Scientists, a longtime opponent of missile defense, argues that any country capable of building long-range missiles would also know how to use decoys and other means of fooling US interceptors.
"There is little or no prospect that the United States will develop a defense system that could defend against real-world, long-range missiles in the foreseeable future," the organization said this month in a critique timed to coincide with the 25th anniversary of Reagan's "Star Wars" speech.
Among those most intimately familiar with the project, retired Air Force Lt. Gen. Ronald Kadish is a firm believer. He was director of the Pentagon's Missile Defense Agency from 1999 to 2004.
"I have every confidence that faced with the basic knowledge of what we've accomplished and how it works and the need for it, people would be willing to continue with it," Kadish said in a recent interview. He quickly added with a small chuckle, "Now, I'm an eternal optimist -- otherwise I wouldn't have been in the missile defense business."
The program may have gained some credibility when an interceptor fired from a Navy ship in late February smashed into a failing US spy satellite in low Earth orbit -- an apparent deadeye success. Hitting a large satellite passing in orbit on a predictable path is different from hitting a missile in flight, but the fact that it was deemed a success probably lent some luster to missile defense.
Compared to the enormously ambitious goal of Reagan's "Star Wars" proposal, which many decried as pie-in-the-sky, the current missile defense program has shrunk in its goals, if not its cost. Reagan foresaw a space-based shield that would be so effective as to render nuclear missiles obsolete.
What has evolved since then is something simpler: a ground-based network of interceptor missiles, radars and communications sites that could defend against attack by just a couple of missiles at a time. The mere existence of such a system -- whatever its proven reliability -- might make it less likely that an unfriendly country like North Korea would even attempt an attack, supporters say.
The first two main sites to be constructed were at Fort Greely, Alaska, where missile interceptors sit in underground silos, and at Vandenberg Air Force Base, Calif., where a second interceptor base was established. They are linked to radars and satellites through communications systems at Colorado Springs, Colo.
The proposed third site would be a combination of 10 interceptors based in Poland and a tracking radar in the Czech Republic. The Bush administration is negotiating with those two governments on terms for such an arrangement; the Russians are opposed but have failed to block it.