The bomb is back as global stockpile grows and risk of nuclear war enters a new age

China's growing stockpile of nuclear weapons is expected to triple by 2035, according to some estimates

- Laurence Norman, Daniel Kiss, Ming Li, & Peter Saidel

At the end of the Cold War, global powers reached the consensus that the world would be better off with fewer nuclear weapons. That era is now over. Treaties are collapsing, some nuclear-arms-control pacts between Russia and the U.S., the Intermediate-Range Nuclear Forces Treaty, has collapsed. The New Start treaty, which placed even tighter limits on the number of deployed warheads on each side and the missiles and bombers that carry them, expires early next year. Senior officials in Washington now say the U.S. needs to be prepared to expand its nuclear force to deter growing threats from Russia and China—raising the potential of a new arms race.

Nuclear powers are strengthening their arsenals; the risk is growing that nuclear weapons will spread more widely and the use of tactical nuclear weapons to gain battlefield advantage is no longer unimaginable. The path to resurgent fears of nuclear war began in 1945, with the first nuclear test blast at the Trinity test site in New Mexico.

In 1963, during the throes of America's Cold War rivalry with the Soviet Union, President John F. Kennedy described his fear of a nuclear age without guardrails, in which dozens of nations possess weapons of mass destruction—what he called the "greatest possible danger and hazard."