Nuclear weapons haven’t been tested in the United States since 1992. Find out why, and what could happen if the hiatus ends.

In 1961, the Soviet Union detonated the largest nuclear weapon ever built, a test so powerful it sent shockwaves around the ...

President Trump said on Thursday that the U.S. would begin testing nuclear weapons again for the first time in decades. “We’ve halted many years ago, but with others doing testing I think it’s ...

The 4 to 7 percent increase in background radiation poses problems for sensitive scientific instruments. Geiger counters, ...

A subsurface atomic test near Yucca Flats, Nev., in March 1955. (U.S. Atomic Energy Commission via AP) In what would be a major shift in a decades-old American policy against global nuclear ...

In a particularly heated moment from his first term, Trump taunted North Korea’s Kim Jong Un — whose 2017 underground test is the last known example of explosive nuclear testing — for the relative ...

President Donald Trump has directed the Pentagon to resume testing nuclear weapons after a 33-year pause, announcing the move on social media just ahead of meeting Chinese President Xi Jinping in ...

Minutes before walking into a high-stakes meeting with Chinese President Xi Jinping this past week, President Donald Trump announced what could prove to be a stunning shift in American nuclear policy.

Prior to his meeting with China’s President Xi Jinping in Busan, South Korea on October 30, United States President Donald Trump wrote that he has ordered the U.S. military to resume nuclear testing ...

President Trump said on Thursday that the U.S. would begin testing nuclear weapons again for the first time in decades. “We’ve halted many years ago, but with others doing testing I think it’s ...