A sub-surface atomic test is shown March 23, 1955 at the Nevada Test Site near Yucca Flats, Nev.
AP/U.S. Atomic Energy Commission
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AP/U.S. Atomic Energy Commission
President Trump made a statement on Thursday regarding the resumption of nuclear weapons testing in the U.S. for the first time in decades.
“We’ve halted many years ago, but with others doing testing I think it’s appropriate to do so,” the president told reporters aboard Air Force One.
Experts say that the resumption of testing would be a major escalation and could upend the nuclear balance of power.
“I think a decision to resume nuclear testing would be extremely dangerous and would do more to benefit our adversaries than the United States,” said Corey Hinderstein, vice president for studies at the Carnegie Endowment for Nuclear Peace.
Here’s what a test would involve, and why the president might be calling for one now.
There’s currently only one place America could test a nuke — near Las Vegas, Nevada
The Nevada National Security Site, approximately 60 miles northwest of Las Vegas, is currently the only place where America could test a nuclear weapon, says Robert Peters, a senior research fellow for strategic deterrence at the Heritage Foundation.
The Nevada site is around 1,300 square miles in size, larger than the state of Rhode Island. Starting in the 1950s, scientists conducted atmospheric nuclear tests at the site, but from 1962 to 1992, testing was done underground.
Today, testing would likely be done in “a complex of deep underground mineshafts,” Peters said.
Scientists dig a deep shaft either directly below ground or into the side of a mountain. They then put a nuclear device in a chamber at the end of the shaft and seal it up. The detonation is contained by the rock, reducing the risk of atmospheric fallout.
Although underground testing is far safer than atmospheric testing, it still carries risks, said Hinderstein. In the past, some radioactive fallout has leaked from test shafts. Additionally, the test could shake buildings as far away as Las Vegas, and Hinderstein said some of the newer buildings in Vegas could even be at risk of damage.
“All of these big highrises — including Stratosphere, including the Trump Hotel,” she said. “They’re not designed for massive, significant seismic activity.”
America’s last test in Nevada was over 30 years ago
At the end of the Cold War, the nation’s major nuclear powers declared a voluntary moratorium on nuclear testing. Russia, then the Soviet Union, tested its last nuclear weapon in 1990, the U.S. conducted its final test in 1992, and China conducted its last test in 1996.

