International Physicians for the Prevention of Nuclear War

Photo from the first U.S. nuclear field exercise on land on Nov. 1, 1951.
Federal Government of the United States / Wikimedia Commons

    

It has been nearly 50 years since the U.S. and the Soviet Union first sat down to talk about limiting their arsenals of nuclear weapons. 

Today, Russia and the U.S. have reduced their stockpiles, but they still have nearly 2,000 warheads each and several other countries have shown interest in creating or expanding their nuclear arsenal. 

So how do we gauge the threat of a nuclear conflict? What would nuclear war look like if it were limited to one region of the world?