Nuclear Weapons: Who Has What at a Glance

At the dawn of the nuclear age, the United States hoped to maintain a monopoly on its new weapon, but the secrets and the technology for making nuclear weapons soon spread.

• Arms Control Association

The United States conducted its first nuclear test explosion in July 1945 and dropped two atomic bombs on the cities of Hiroshima and Nagasaki in August 1945.

Just four years later, the Soviet Union conducted its first nuclear test explosion. The United Kingdom (1952), France (1960), and China (1964) followed.

Seeking to prevent the nuclear weapon ranks from expanding further, the…

• Nuclear Weapons: Who…