© Mass Communication Specialist 1st Class Ashley Berumen/Commander, Submarine Group Ten/U.S. Navy The Ohio-class ballistic-missile submarine USS Tennessee arrives at the Trident Refit Facility dry dock at Naval Submarine Base Kings Bay, Georgia, for a maintenance period, August 13, 2019. The vessel is capable of carrying up to 20 submarine-launched ballistic missiles with multiple warheads, one or two of which are believed to be equipped with the W76-2 warhead, according to the Federation of American Scientists.

Russia has criticized the Trump administration's pursuit and deployment of low-yield nuclear warheads, arguing it may raise the prospects of a nuclear conflict. At the same time, however, the United States estimates its top foe has up to 2,000 such warheads.

Russian Foreign Minister Maria Zakharova on Friday blasted the $28.9 billion budget proposed for the Pentagon's nuclear modernization program, along with the additional $15.6 billion earmarked for the Department of Energy National Nuclear Security Administration's efforts to revamp the U.S. nuclear warhead arsenal. Among the weapons being developed and deployed is the W76-2, a nuclear warhead with lower yields that Zakharova and others contend could make them a more readily-available option in the event of a conflict.

"We note that Washington is not just modernizing its nuclear forces, but is striving to give them new capabilities, which significantly expands the likelihood of their use," Zakharova told a press conference.

"Of particular concern in this regard are U.S. actions to increase the range of low-power assets in its nuclear arsenal, including the development and deployment of such munitions for strategic carriers. This clearly leads to lowering the 'threshold' for the use of nuclear weapons," she added.

But the concept of low-yield nuclear weapons dates back to the Cold War, and both countries have developed such capabilities.

A Pentagon spokesperson told Newsweek that "Russia currently has approximately 2,000 non-strategic, low-yield nuclear weapons. This includes nuclear torpedoes, nuclear air and missile defense interceptors, nuclear depth charges, nuclear landmines, and nuclear artillery shells—more than a dozen types. None of these are limited by any current arms control treaties."

"If Russia believes the W76-2 lowers the threshold for nuclear use, then it must explain why its own non-strategic, low-yield nuclear weapons don't likewise increase the likelihood of a conflict going nuclear," the spokesperson said. "It is more likely that Russia recognizes the W76-2 deployment as a demonstration of U.S. resolve, thereby contributing to deterrence of any nuclear attack."

The U.S. and Russia have long accused one another of developing tactical nuclear devices, perhaps less destructive than their larger counterparts but still extremely more powerful than even the most earth-shattering conventional munitions. The five-to-seven-kiloton W76-2 may produce a third of the detonation force of the relatively primitive atom bomb dropped on Hiroshima in 1945, but explodes with up to 500 times the strength of the Massive Ordnance Air Blast, or "Mother of All Bombs (MOAB)."

The W76-2 warhead was revealed in last year's budget as part of the Trump administration's 2018 Nuclear Posture Review. "Expanding flexible U.S.

nuclear options now, to include low-yield options, is important for the preservation of credible deterrence against regional aggression," the document noted, accusing Russia of pursuing its own low-yield warhead program.

© Russian Ministry of Defense The Russian military tests the Avangard hypersonic glide vehicle at the Dombarovsky Air Base near near Yasny in Russia's Orenburg province, December 26, 2018. The weapon was said capable of traveling more than 20 times the speed of sound, delivering a missile faster than any existing defense. Russian Ministry of Defense

In January, Newsweek reported that the W76-2 had been fielded, armed to a Trident II submarine-launched ballistic missile (SLBM). The following month, the Pentagon announced that the low-yield warhead had been deployed as part of the Trump administration's efforts "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."

The Pentagon also announced last year that it would be looking into developing a nuclear-armed sea-launched cruise missile (SLCM-N). Both W76-2 and the SLCM-N "are measured responses to close gaps in regional deterrence that have emerged in recent years," the Pentagon spokesperson told Newsweek.

"The employment of the W76-2 has not changed the United States' threshold for using nuclear weapons," the spokesperson said. "Rather, it raises the threshold for nuclear use by potential adversaries by addressing adversary perception of advantage, improves our nuclear deterrent, allows the U.S. to negotiate from a position of strength, and brings an enhanced assurance element to our allies."

As for the Pentagon itself, the nuclear-related portion of its $705 billion budget for 2021 includes funds devoted to revamping nuclear command, control and communications, the new Columbia-class ballistic missile submarine, the B-21 Long-Range Strike Bomber, Long-Range Stand-off Missile and the Ground-Based Strategic Deterrent.

Speaking frankly at his testimony to the House Armed Services Committee last week, Joint Chiefs of Staff Chair Army General Mark Milley again brought up Russia as the top priority for U.S. nuclear modernization efforts. "They are the only country on the Earth that represents a, no kidding, existential threat to the United States," he told lawmakers.

"Every man, woman and child can be killed by the Russians, and we can do the same, hence deterrence," Milley added. "Maintaining a guaranteed nuclear enterprise is critical relative to Russia. With respect to China, their nuclear enterprise is growing rapidly."

The Pentagon spokesperson agreed, but noted that "the U.S. is not attempting to match or counter adversaries system for system." Instead, "modifying a small number of existing SLBMs addresses the imbalance in non-strategic nuclear weapons and ensure our deterrence remains strong in the face of the changing nuclear environment with both Russia and China," the spokesperson said.

But Moscow has dismissed this line of reasoning, arguing that Washington was the clear aggressor.

At a Pentagon press briefing last month, U.S. defense officials revealed that the U.S. military had conducted a "mini-exercise" simulating a scenario in which "Russia decides to use a low-yield limited nuclear weapon against a site on NATO territory." The U.S. hit back with a simulated nuclear strike one official only characterized as "limited" in nature.

Russia responded to the revelation with outrage, accusing the U.S. of fear-mongering and normalizing nuclear war with the "sick" exercise. On Friday, Zakharova further castigated the U.S. approach to nuclear modernization, telling reporters: "One gets the impression that in Washington they have decided to purposefully consider nuclear conflict as a viable political option and create the corresponding potential for this."

She accused the U.S. of trying to justify its actions by blaming Russia and China. "We consider such plans destabilizing," Zakharova argued. "A much more effective way to ensure national security is to continue the policy of arms control and establish peaceful interaction with other states, to which we again call on the United States."

The Trump administration abandoned the Intermediate-range Nuclear Forces (IN) Treaty in August, after accusing Moscow of developing a banned missile capable of traveling within the 310- to 3,420-mile restricted range. The president has also dismissed Russian attempts to extend their bilateral New Strategic Reduction Arms Treaty (START), unless a new warhead-limiting framework was established involving new platforms like hypersonic missiles and additional countries such as China.

The State Department reiterated this offer for a trilateral arms arrangement Thursday on the 50th anniversary of the Non-Proliferation Treaty, but Chinese Foreign Ministry spokesperson Zhao Lijian rejected it. Beijing, which has significantly less nuclear warheads than Moscow and Washington, seeks multilateral cooperation, but not limitation.

"China has repeatedly reiterated that it has no intention of participating in the so-called trilateral arms control negotiations with the U.S. and Russia. This position is very clear," Zhao said Friday. "The pressing issue on nuclear disarmament at the moment is for the United States to respond to Russia's call to extend the New START Treaty, and further downsize its huge nuclear arsenal. This will create conditions for other nuclear weapon states to join multilateral disarmament talks."

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