For the past few years, the Bush administration has tried to keep a military R&D program as much in the background as possible. There was serious planning on the next generation of nuclear weapons, known as 'bunker busters,' that would be based on miniature nuclear explosions after a missile or bomb penetrated into the ground. As long as there was research being done on such weapons, many scientific organizations jumped in arguing that there were serious consequences to the use of such weapons, as well as serious diplomatic and political ramifications such as possible cold wars reappearing with other nations, such as China. Some of the consequences on the battlefield included the large amounts of radioactive debrs that would go airborne after the explosion, and wind-shifts could in fact expose our own troops to the fallout. In addition, computer simulations showed that if such explosions occurred near cities, potentially tens of thousands of civilians would be exposed to cancer-causing agents.
Fortunately, Congress finally got the message and is set to stop the funding of this program. Kudos to them for this move, which I have argued for in letters and online for a couple years.