. E. WARREN AIR FORCE BASE, Wyo. ? As the military girds for a protracted war against terrorists and the countries that support them, the Pentagon is considering converting some of its long-range, ground-based nuclear missiles into nonnuclear rockets that could be used to strike states like Iraq and North Korea on short notice.
The weapon would give the United States the ability to attack targets thousands of miles away with precision-guided, conventional high explosives in minutes, military officials said. Because of the missiles' speed, they would be able to pierce current air defenses and avoid putting American pilots at risk, they added.
Replacing nuclear warheads with conventional weapons on some of the nation's globe-girdling missiles is a proposal that is barely on the drawing board. The Air Force Space Command in Colorado Springs will begin formally exploring the idea of converting some Minuteman III missiles this fall in a two-year review the military calls an "analysis of alternatives."
But senior Air Force and Pentagon officials are seriously weighing the proposal as part of a larger rethinking of the kind of deterrence and long-range attack weapons the military will need in the security environment that followed the attacks of Sept. 11, 2001.
"I'd be very, very surprised if 5, 10 years down the road, that we would not have a ballistic missile of some type with conventional munitions on board so that it could serve the nation's needs for a prompt global strike," said Maj. Gen. Timothy J. McMahon, commander of the 20th Air Force here, which runs and maintains the nation's silo-based arsenal of 500 long-range Minuteman III and 45 Peacekeeper nuclear missiles.
"If the nation decides that it wants to place at risk certain targets that emerge, and that if you need to strike those things in a very prompt manner ? 35 to 45 minutes ? a ballistic missile gives you that capability," General McMahon said. "It's basically long-range artillery. But the type of munition on board would be unlike any other artillery we've ever used."
General McMahon said the conventional warhead atop a long-range missile could be drawn from an array of high explosives or specialized payloads, including so-called bunker busters that attack targets buried deep underground.
Even without an explosive payload, the sheer force of impact of the missile's re-entry vehicle ? which moves at 14,000 feet per second ? would be highly destructive, the general said.
Arms control experts are wary of the military's proposal. Converting nuclear missiles to nonnuclear missiles would reduce the overall number of strategic weapons, but there would be no assurances that the military would not someday rearm the missiles with nuclear weapons, a move that other countries could follow.
"It could elicit a response from other missile powers, like China or Russia," said Daryl G. Kimball, executive director of the Arms Control Association in Washington.
Other political and diplomatic hurdles would have to be cleared. Pentagon officials say they expect that any long-range missiles with conventional arms would be counted under existing arms control agreements, including the Strategic Arms Reduction Treaty, or Start.
The military has considered using Minuteman III missiles in a conventional role before, but the latest proposal comes as the Bush administration has overhauled its nuclear strategy to adapt to shifting world situations.
The Pentagon argues that in a world of unexpected threats and hostile states, it needs a broader array of nuclear and nonnuclear options.
Last March, details emerged from a secret Pentagon report, the Nuclear Posture Review, that addressed these issues. On the one hand, the report called for developing nuclear weapons that would be better suited for striking targets in Iraq, Iran, North Korea, Syria and Libya, a shift away from cold war situations involving Russia.
But the Pentagon report also found that nonnuclear conventional weapons were becoming an increasingly important element of the military's arsenal, to be used in what planners call long-range global strikes. Now, the military depends on piloted Air Force and Navy bombers or unmanned cruise missiles fired from planes, ships or submarines to attack targets.
Strategists in the Air Force, Defense Department and the United States Strategic Command in Omaha are also using the report to mull over ways to convert the nation's nuclear arsenal into weapons that could be used to deter the use of chemical, biological or nuclear weapons, or destroy them on short notice.
"In many ways, we'd be taking a legacy of the cold war and adapting it in the direction the Nuclear Posture Review described," said a senior Defense Department official who follows nuclear policy closely.
The Bush administration has said that it plans to reduce strategic nuclear weapons to 1,700 to 2,200 warheads from the 6,000 or so nuclear weapons that the United States has now.
Here on the windswept high plains of southeastern Wyoming, the reductions are already under way. Beginning last fall, Air Force technicians started dismantling the Peacekeeper missiles, each armed with up to 10 nuclear warheads, as part of a nuclear-force reduction agreement that President Bush and President Vladimir V. Putin of Russia reached last year. The Peacekeepers will be deactivated over the next three years.
At the same time, the fleet of single-warhead Minuteman III's, stored in underground silos across Wyoming, Colorado, Nebraska, Montana and North Dakota, is being modernized to improve accuracy and reliability.
While nuclear deterrence remains commanders' top priority, the new proposal could push the military's strategic operators in a different direction.
"It's quite possible that the conventional application of that kind of technology will be an attractive option for the future," said Gen. Lance W. Lord, commander of the Air Force Space Command. "How these plans will emerge and how combatant commanders will choose to use those is something we'll think about."