Iraq's surprise invasion of Kuwait in August 1990 raised once again the issue of use of nuclear weapons. Iraq's extensive conventional capabilities, past history of chemical-arms use, known interest in acquiring nuclear weapons, and revisionist ambitions, made it a textbook case of a post-Cold War Third World adversary. The United States ultimately deployed 500,000 troops to Kuwait in the fastest, farthest, and largest military deployment in the country's history, fought a 35-day air war and a 4-day ground war to defeat Iraq. US leaders ruled out using nuclear weapons even though Iraq was a non-nuclear adversary.

It might be argued that the Gulf War does not offer a good test of the nuclear taboo because the kind of dire circumstances that would call up consideration of a nuclear option never really emerged for the United States and its coalition allies. Nevertheless, this case is significant. It represents the first major conflict of the post-Cold War world, when the threat of nuclear confrontation with the Soviet Union had largely evaporated. At the time, Iraq wielded the world's fourth largest conventional army.