U.S. Studies Foam Bombs Among Options to Isolate Chemical Weapons

Defense researchers are pursuing novel ways to disable chemical and biological weapons, including a missile that would isolate weapon storage sites by coating them in an impenetrable foam.

The foam bomb is one of several weapons on the drawing board that could include toxic or other materials loaded on an earth-penetrating warhead. The idea is to neutralize, rather than blow up, underground storage sites for weapons of mass destruction, Stephen M. Younger, director of the Pentagon’s Defense Threat Reduction Agency, said Wednesday.

The approach would enable U.S. forces to isolate chemical and biological weapons in urban areas without bombing them, which carries the risk of releasing chemical or biological agents into the atmosphere, endangering soldiers and civilians.

Work on the concept comes as the Bush administration weighs an invasion of Iraq that, military analysts say, would leave President Saddam Hussein with little to lose by unleashing weapons of mass destruction on an invading U.S. army whose goal would be his removal.

Defense officials also voice concern that terrorists could team up with Iraq or other nations with the capacity to develop chemical, biological, or even nuclear weapons. Iraq, listed by the State Department as a state sponsor of terrorism, is believed to have furthered its research into chemical and biological weapons since the Gulf War and has shown a keen interest in developing nuclear weapons, Younger said.

U.N. weapons inspectors believe Hussein has placed arsenals of the taboo weapons beneath hospitals in urban Baghdad. Some of the devices under consideration by the Pentagon could kill organic agents in an enclosed space with intense and extended heat. Among the more controversial weapons are nuclear-tipped missiles designed to penetrate deep into the earth.

Some concepts remain years away, likely too late for an invasion of Iraq. But Younger suggested researchers are close to beginning development on others.

“The component technologies are there. The basic research has been done,” Younger said. “It may not be years [away] in some cases.”

But he said more work needs to be done on key technologies allowing soldiers to detect chemical and particularly biological weapons at a safe distance.

Detection of chemical and biological weapons has improved since the Gulf War and soldiers deployed in Iraq would be given chemical suits and probably vaccines for smallpox and other diseases. Yet the risks are “still unacceptably high” for soldiers, Younger said, largely because reliable detection systems that can pinpoint multiple agents at a distance are still being developed.

Younger’s agency, based at Ft. Belvoir, Va., is charged with developing ways to deter nuclear assaults and reduce the threat from all types of weapons. The agency, part of the Department of Defense, has also been consulted for domestic strategy as the Bush administration creates the Department of Homeland Security.

One common theme is the need for weapons that penetrate deep into the ground.

“Deeply buried, hardened targets are sort of the target of choice right now,” said Clark Murdoch, a former Air Force director for planning who is now with the Center for Strategic and International Studies, a foreign policy think-tank.

That priority stems not only from intelligence on the location of weapons sites in Iraq but experience in the war in Afghanistan. U.S. warplanes, targeting pro-Taliban fighters hiding in caves and tunnels, dropped the first earth-shuddering thermobaric explosive, the BLU-118, in the mountains in March. The device sends a slow-release pulse of destructive energy deep below the earth surface.

Classified documents call for exploring the development of nuclear-tipped missiles. While the concept has been criticized for its potential to lower the threshold for nuclear attacks or to launch a new nuclear small arms race, defense officials think modifying weapons might be less controversial.

Under one scenario, for example, a B-61--a bomb that can be modified to deliver varying amounts of explosive power--could be used to penetrate underground bunkers.

“The B-61 warhead is the only nuclear weapon at this time that’s configured for any kind of penetration before it explodes,” Murdoch said.

But military analysts say it remains unclear how deep such a weapon would have to go to reduce the spread of radiation to acceptable levels.