Navy Deploys Low-Yield Nuclear Warhead in SLBMs, Pentagon Confirms

An unarmed Trident II missile launches from the Ohio-class ballistic missile submarine USS Nebraska off San Diego in September. The Pentagon confirmed that the W76-2 low-yield nuclear warhead is now deployed on the Trident. U.S. Navy

ARLINGTON, Va. — The U.S. Navy has deployed the W76-2 low-yield nuclear warhead in the Trident submarine-launched ballistic missile, the Defense Department confirmed Feb. 4. 

The deployment was reported in an article posted Jan. 29 on the website of the Federation of American Scientists (FAS) by William M. Arkin and Hans M. Kristensen and has been confirmed by John Rood, undersecretary of defense for policy. 

“The Navy has fielded the W76-2 low-yield submarine-launched ballistic missile warhead,” Rood said in the statement. 

“In the 2018 Nuclear Posture Review, the department identified the requirement to ‘modify a small number of submarine-launched ballistic missile warheads’ to address the conclusion that potential adversaries, like Russia, believe that employment of low-yield nuclear weapons will give them an advantage over the United States and its allies and partners. 

“This supplemental capability strengthens deterrence and provides the United States a prompt, more survivable low-yield strategic weapon; supports our commitment to extended deterrence; and demonstrates to potential adversaries that there is no advantage to limited nuclear employment because the United States can credibly and decisively respond to any threat scenario.” 

The FAS article claimed that the W76-2 is believed to have been deployed in late 2019 on the USS Tennessee, an Ohio-class ballistic-missile submarine based at Naval Submarine Base Kings Bay, Georgia. FAS said the W76-2 has a nuclear yield equivalent of five kilotons of explosives, compared with 90 kilotons for the W76-1 warhead and 455 kilotons of the W88 warhead.  

The low-yield warhead became a point of dispute between Democrats and Republicans in the Congress, with Democrats opposing the deployment, voiced by House Armed Services Committee Chairman Adam Smith (D-Wash). In the fiscal 2020 National Defense Authorization Act passed into law in December, the warhead survived conference committee negotiations and was approved for deployment.