The outgoing vice chairman of the Joint Chiefs on Tuesday called development of a low-yield nuclear weapon a required necessity to fill a current nuclear deterrence capability gap, as the debate over banning funding of the weapon has picked up on the Hill.

Air Force Gen. Paul Selva told reporters he supports adding the W76-2 low-yield, submarine-launched, ballistic missile warhead to the U.S.’ inventory as a means to respond in equal measure to a potential nuclear escalation with Russia, which already has such a capability.

Gen. Paul Selva, Vice Chairman of the Joint Chiefs of Staff, speaks at the Defense Writers Group breakfast. Photo: GW’s Project for Media and National Security

 “What we’ve tried to do with the introduction of low-yield nuclear weapons is fill a hole that exists in the potential escalation ladder that we know is part of Russian doctrine,” Selva told the Defense Writers Group. “Our doctrine says that we will respond in kind. Without a low-yield nuclear weapon in our inventory, responding in kind means we have to respond with a high-yield nuclear weapon, which many would argue is disproportionate.”

Selva called arguments a low-yield weapon would produce a redundant capability or would diminish the current capacity of the Trident missile “unsophisticated and ill-informed.”

“I could ask the same question only in reverse. How are we supposed to know that a cruise missile that’s launched off of a Russian vessel towards the United States is a high-yield or low-yield weapon? That answer is we won’t know until it detonates,” Selva said.

Last week, the House Armed Services Committee approved its mark of the FY ’20 NDAA following lengthy debate over a series of amendments including one by Rep. Liz Cheney (R-Wyo.) that would have reversed a ban on the funding for the low-yield nuclear weapon (Defense Daily, June 13).

The amendments failed along party lines, and HASC’s proposed bill moves forward with a provision banning the Navy from deploying such a weapon.

“I acknowledge that this has caused us political tension on our budget, and it’s an issue that we’re going to have to work our way through. But I’m not in a position to yield on the efficacy of having it in the inventory,” Selva said.

Selva said the U.S. currently does not have a conventional weapon or combination of weapons that would create the same outcome as a low-yield weapon, noting that concepts such as hypersonics or nuclear-armed Tomahawk missiles remain hypothetical.