The U.S. Navy has deployed new low-yielding nuclear weapons aboard the submarine USS Tennessee in the Atlantic Ocean, according to the Federation of American Scientists (FAS).
The FAS, which independently monitors nuclear activity, claimed that there are “one or two” aboard the submarine and they could also be aboard a second submarine in the Pacific Ocean.
“It is apparently still out there now and expected to come back sometime in February,” said the director of the group’s nuclear information project, Hans Kristensen.
The Pentagon would not confirm their existence, per U.S. policy, according to a statement reported by NPR.
“It is U.S. policy to neither confirm nor deny the presence or absence of nuclear weapons at any general or specific location, as such, we cannot confirm or deny this reporting at this time,” the Pentagon said.
The weapon, known as the W76-2, reportedly has a yield of about five kilotons, about one-third the size of the nuclear weapon dropped on Hiroshima.
The W76-2 was developed by the Department of Energy over the past year and a spokesman for the department confirmed to NPR that they transferred the warhead to the Navy.
The Energy Department developed the warheads as part of the Trump administration’s Nuclear Posture Review, which it unveiled in February 2018.
When the administration unveiled the Nuclear Posture Review, it was described as a way to “help counter any mistaken perception of an exploitable ‘gap’ in U.S. regional deterrence capabilities,” which the Federation of American Scientists says is a reference to Russia.
The Federation of American Scientists estimates that when the U.S. developed 50 W76-2s, they were created as a response to Russia lowering its threshold for first-use tactical nuclear weapons in a limited regional conflict.
“W76-2 will allow for tailored deterrence in the face of evolving threats” and gives the United States “an assured ability to respond in kind to a low-yield nuclear attack,” the National Nuclear Security Administration explained.
One problem faced with potentially using a W76-2 is it looks identical to the W76-1, which is a conventionally sized warhead, and Russia wouldn’t be able to determine which one was used, prompting a greater response in retaliation.
“Once you start popping nukes, the bets are off,” Kristensen warned.
Katarzyna Zysk, who studies Russian military doctrine at the Norwegian Institute for Defence Studies in Oslo, said that Russia has made a number of vague statements about nuclear use, and has deployed several systems that are nuclear-capable.
There is also evidence that Russia has conducted military war games practicing early nuclear use in a European conflict, according to the Federation of American Scientists.
“[Russian President Vladimir] Putin may well believe that the United States would not respond with strategic warheads that could cause significant collateral damage” and “Moscow could conceivably engage in limited nuclear first-use without undue risk,” consultants involved in producing the Nuclear Posture Review said.