11.   An aggrieved group that decides it wants to kill huge numbers of Americans will find the mission easier to accomplish with anthrax than with a nuclear explosion.

12.   And at least one senator has raised questions about whether tiny nuclear explosions to be triggered by the lasers would violate the Comprehensive Test Ban Treaty.

13.   And nuclear explosions deep underground make telltale depressions at the surface, the tracking of which could aid arms control.

14.   Arms controllers worry that even without real nuclear explosions, weapons scientists will make remarkable progress, using new tools like computer-simulated bomb blasts.

15.   Arms control advocates fear that the Comprehensive Test Ban Treaty, barring nuclear explosions, may be next in line.

16.   Both the United States Army and Air Force operated networks of secret stations around the globe to listen for the nuclear explosions.

17.   A direct hit from a commercial jetliner would not cause a nuclear explosion, officials at the agency said.

18.   A subnuclear experiment, which would not involve a nuclear explosion, might not have the political effect of a full-fledged detonation.

19.   A team of scientists from the Department of Energy Wednesday strongly backed the recently proposed idea that atomic wastes buried deep underground might erupt in a nuclear explosion.

20.   After India set off five underground nuclear explosions earlier this week, Clinton cut off all U.S. financial aid, except humanitarian assistance.