The end of the cold war and the dissolution of the Soviet empire changed, but did not eliminate, the nuclear threat to the United States.

Other countries who previously had the weapons but did not have weapon delivery vehicles able to reach the United States now have the ability to do so.

Improvised nuclear devices (IND) (radioactive material placed inside a conventional explosive device) are becoming increasingly possible. These IND weapons may someday be within a terrorist's ability to employ.