President Donald Trump boasted in a tweet Monday evening that the United States had “more advanced” missiles than Russia, following a rocket explosion in the country that left five nuclear engineers dead.

If his tweet is accurate, it suggests the United States has technology thought to have been abandoned over half a century ago. It also means the president may have revealed classified information about weapons that the U.S. military may currently possess.

Some experts believe the president may have simply been making things up once again.

“The United States is learning much from the failed missile explosion in Russia. We have similar, though more advanced, technology,” Trump tweeted Monday, referencing the incident at a military test site in northern Russia last week that killed five employees of the nation’s atomic agency, Rosatom.


That explosion caused a spike in radiation in the region, though officials dismissed health concerns, saying the levels did not pose any danger to local residents. Trump on Monday, however, claimed that the explosion “has people worried about the air around the facility, and far beyond. Not good!”

The technology the Russians were testing was described by Rosatom as a “nuclear isotope power source” for a rocket engine. Details of the accident as provided by Russian authorities have continued to shift in the days since.

Trump appeared to confirm in his tweet Monday that Russia was testing what NATO has referred to as “Skyfall,” Russia’s experimental nuclear-powered cruise missile.

Trump’s assertion that the United States has “similar, though more advanced, technology” caused alarm and confusion among defense experts. Not only does this appear to reveal classified military information, but it also contradicts a historical understanding that the United States abandoned such research in 1964.

Joe Cirincione, president of the nuclear nonproliferation Ploughshares Fund and author of Nuclear Nightmares, gave context for the history of these failed experiments in a tweet Monday evening.


“This is bizarre,” he wrote. “We do not have a nuclear-powered cruise missile program. We tried to build one, in the 1960’s, but it was too crazy, too unworkable, too cruel even for those nuclear nuts Cold War years.”

This is bizarre. We do not have a nuclear-powered cruise missile program. We tried to build one, in the 1960's, but it was too crazy, too unworkable, too cruel even for those nuclear nuts Cold War years. https://t.co/DWMn07yO3Y https://t.co/7Uqpx7B7Sk — Joe Cirincione (@Cirincione) August 12, 2019

As he later explained to MSNBC, the United States once pursued “Project PLUTO,” a missile that would have contained an unshielded nuclear reactor, spewing radiation everywhere it went. Researchers concluded such a weapon was “too cruel, too insane, too ridiculous,” and was unnecessary, as Cirincione described it.

The Skyfall missile would be different from this, in that it would merely be powered by a nuclear reactor and is hypothetically not designed to spread radiation everywhere it travels. The exception, of course, is when it explodes, as evident from the radiation spread by the accident that took place last week.

While it seems unlikely that the United States has secretly continued to pursue some form of this technology, some national security experts are still concerned about Trump’s facile references to the nation’s military capability.


Stephen Schwartz, a senior fellow at the Bulletin of the Atomic Scientists, was doubtful of Trump’s claims. But he noted that if the United States was truly pursuing such technology, it must be a “highly classified program.” Like Cirincione, he decried the efforts of Project PLUTO, calling the project “stupid, unnecessary, and extremely hazardous.”

we abandoned this weapon concept (Project PLUTO and the Supersonic Low-Altitude Missile or SLAM) in 1964 because it was stupid, unnecessary, and extremely hazardous, especially to our allies, over whose territory it would have to fly to reach targets inside the Soviet Union. 2/2 — Stephen Schwartz (@AtomicAnalyst) August 12, 2019

The tweet likewise raised big red flags for foreign policy scholars like Michael McFaul, former ambassador to Russia, and David Burbach, associate professor at the U.S. Naval War College.

“It is a bad idea for the President to tell the world the U.S. has secret nuclear powered super-weapons and that we’ve been lying about that for years. Especially if we don’t actually have them, which we almost certainly do not,” Burbach tweeted.

It is a bad idea for the President to tell the world the U.S. has secret nuclear powered super-weapons and that we've been lying about that for years. Especially if we don't actually have them, which we almost certainly do not. https://t.co/pK0sNPRpeg — David Burbach (@dburbach) August 12, 2019

“We have similar technology? Nuclear-powered cruise missiles? I wasn’t read into that program when I worked at the National Security Council. Can anyone shed more light?” McFaul tweeted separately.

ThinkProgress reached out to the Department of Defense, which declined to comment both on what weapons the country possesses and the implications of Trump’s tweet — referring any questions specifically about the Skyfall explosion to Russia.

ThinkProgress also reached out to the National Security Council for comment, but had not heard back at the time of publication.