US 'Low-Yield' Nuclear Weapons: Increase or Decrease the Risk of War?

“New milestone”

The first deployment of this weapon on long-range nuclear submarines is a milestone in US nuclear weapons policy, according to the AP news agency. This is the first major addition to the US strategic nuclear arsenal in recent decades, and gradually moves away from the Obama administration's policy of reducing dependence on nuclear weapons in pursuit of a world without nuclear weapons.

Trident D5 missile during a test launch. Photo: US Navy

Confirming the deployment of the new missile to reporters, a senior Pentagon policy official asserted that the weapon would make Americans safer by reducing the likelihood of nuclear war.

John Rood, the Pentagon’s undersecretary of defense for policy, said in an interview on February 3 that adding the “low-yield” W76-2 warhead to submarines carrying Trident II ballistic missiles would reduce the likelihood of nuclear war. He affirmed that the US would continue its stated policy of using nuclear weapons only in “unusual circumstances.” He also said that the new warhead would help the US discourage Russia from risking a limited nuclear conflict.

“This additional capability enhances deterrence and provides the United States with a more survivable, immediate low-yield strategic weapon,” Rood said, adding that the weapon supports the US commitment to deter attacks against allies, and “demonstrates to potential adversaries that limited nuclear deployments are of no advantage because the United States can respond to any threat scenario credibly and decisively.”

The US Navy's ballistic missile submarine USS Wyoming. Photo: AP

However, Mr. Rood refused to provide details about the deployment, including the time and location; and he emphasized that all details are confidential. The US press has so far only grasped that the information about the deployment of the new weapon was reported by the Federation of American Scientists last week, citing anonymous sources and saying that the deployment of the new weapon began in the final weeks of 2019, along with the deployment of the destroyer USS Tennessee in the Atlantic.

Although US President Donald Trump has not commented on this weapon, observers say that the addition of the W76-2 is consistent with the concern that the White House owner has mentioned, which is to strengthen nuclear weapons. The Trump administration has always wanted to modernize on a larger scale, even though it is costly for the country's nuclear power.

President Donald Trump has pledged to strengthen the US nuclear arsenal. Photo: AP

Increased risk of nuclear war?

As expected, critics, including some Democrats in Congress, see the move as a dangerous overreach that increases the risk of war. The core argument against low-yield weapons is that they make the world less safe by giving policymakers another option to use nuclear weapons in a conflict that could escalate into all-out nuclear war. They also argue that the low-yield air-launched nuclear weapons currently in the US arsenal would make the W76-2 redundant. But Rood says that low-yield submarine-launched missiles are important because they can better penetrate air defenses than nuclear-armed aircraft.

The W76-2 is seen as the Trump administration’s response to what it calls Russia’s mistaken notion of an exploitable “gap” in America’s nuclear capabilities. By deploying sea-based missiles with lower nuclear yields, or destructive power, the administration wants Moscow to stop assuming it could “win” a war in Europe, for example, by launching its own low-yield nuclear weapons first, forcing Washington and its NATO allies to either engage in all-out nuclear war or surrender.

W76 nuclear warhead deployed by the US. Photo: Pantex Plant

The destructive power of the W76-2 has been classified. Experts say it could be around 5 kilotons, or about one-third the destructive power of the “Little Boy” nuclear bomb that the United States dropped on Hiroshima, Japan, in the final days of World War II, killing tens of thousands of people.

In fact, the missiles deployed on US strategic submarines for decades carry the 90-kiloton W76 warhead and the 475-kiloton W-88 warhead. The newly deployed warhead is based on the W76, compatible with an unknown number of Trident ballistic missiles on the US Navy's Ohio-class submarines.

The latest addition to the arsenal comes amid significant changes in the US-Russia strategic relationship, with growing doubts about whether the Trump administration will accept Moscow’s request to extend the New START arms control treaty, the only remaining treaty limiting the number of strategic nuclear weapons held by Russia and the US, before it expires in February next year.

The New START arms control treaty is the only treaty still in force that limits the number of strategic nuclear weapons held by Russia and the United States. Illustration: A Russian S-400 Triumph air defense missile system parades through Red Square. Photo: Getty Images

The Pentagon insists that deploying the new low-yield missiles will not increase the total number of US weapons under the New START limit, since each warhead replaces a more powerful version previously deployed on submarines. But more cautious voices, such as Bruce Blair, a former US Air Force nuclear weapons officer and co-founder of Global Zero, an organization that advocates for the elimination of nuclear weapons, appreciate the reduction in the destructive power of nuclear arsenals, but still emphasize: “We cannot afford to think that lower-yield nuclear weapons can be used more in a conflict. Any use of these sea-based weapons, even for the first time or a second time, would risk igniting a conflict and escalating it to a full-blown nuclear war.”