The Pentagon’s decision to deploy a new low-yield nuclear warhead has been described as “alarming” by a senior Russian diplomat.
The W76-2 warhead, which has an explosive yield of five kilotons—significantly smaller than other warheads—aims to address potential adversaries, such as Russia, who “believe that employment of low-yield nuclear weapons will give them an advantage over the United States and its allies and partners,” John Rood, Under Secretary of Defense for Policy said on Feb. 4.
“Russia’s nuclear modernization program covers every leg of its strategic triad and includes modern intercontinental ballistic missiles, submarine launch ballistic missiles, and long-range strategic bombers,” Rood said.
The first ballistic missile submarine that deployed with the new warhead was the USS Tennessee (SSBN-734), during the final weeks of 2019 in Georgia, reported Federation of American Scientists (FAS). FAS estimates that approximately 50 W76-2 warheads have been produced. However, the Pentagon has not specified where and when they were deployed, reported the Wall Street Journal.
The new warhead acts as a deterrent by “creating uncertainty in the mind of any potential adversary, whether it be Russia or China or anyone else,” David Trachtenberg, Deputy Under Secretary of Defense for Policy, Department of Defense, said in a March 2019 hearing (pdf).
In response, Russia’s Deputy Foreign Minister Sergei Ryabkov said on Feb. 7 that the deployment of the W76-2 warhead in the name of strengthening deterrence had caused Russia great concern over U.S. nuclear strategy, reported Reuters.
“The appearance on strategic carriers of low-power warheads means arguments previously voiced by the American side about the possible use of such a device are now being realized in metal form, as products,” Ryabkov said. “This reflects the fact that the United States is actually lowering the nuclear threshold and that they are conceding the possibility of them waging a limited nuclear war and winning this war. This is extremely alarming.”
The 2018 Nuclear Posture Review (pdf) identified the need for the U.S. to develop a new nuclear arsenal, which was “long past due.”
“While we will be relentless in ensuring our nuclear capabilities are effective, the United States is not turning away from its long-held arms control, non-proliferation, and nuclear security objectives,” the review states.
One tactical advantage to the new warhead is to have a targeted nuclear response in the event the U.S. is attacked with nuclear weapons, according to the review.
“This is a comparatively low-cost and near term modification to an existing capability that will help counter any mistaken perception of an exploitable ‘gap’ in U.S. regional deterrence capabilities.”
The U.S. formally withdrew from the Intermediate-range Nuclear Forces (INF) Treaty with Russia on Aug. 2, 2019. President Trump said that Russia wasn’t complying with the treaty, including failing to comply with requests to destroy its 9M729 ballistic missiles, which the United States said violated the pact.
The U.S. also appears reluctant to extend the New START treaty, (Strategic Arms Reduction Treaty) the last remaining arms control deal between Russia and the United States, which expires in 2021.
In a March 2019 hearing (pdf), General John Hyten of the United States Strategic Command said that both Russia and China had long studied the United States’ way of warfare.
“They [China and Russia] understand and seek to counter our long-held advantages. They are actively exploring new methods to exploit perceived vulnerabilities, and they are directly challenging us in areas of long-held strength,” Hyten said.
Trachtenberg added: “Our nuclear deterrent underwrites all U.S. military operations and diplomacy across the globe. It is the backstop and foundation of our national defense. A strong nuclear deterrent also contributes to U.S. non-proliferation goals by eliminating the incentive for allies to have their own nuclear weapons.”
Zachary Stieber and The Associated Press contributed to this report.