Giving Putin the nuclear advantage

This weapon is aimed at repelling a known risk: Russia’s up to 2,000 tactical nuclear weapons, including weapons that “can be deployed by ships, aircraft and ground forces,” according to the Pentagon’s 2018 Nuclear Posture Review. The Russian nuclear inventory includes “air-to-surface missiles, short-range ballistic missiles, gravity bombs and depth charges for medium-range bombers, tactical bombers and naval aircraft, as well as anti-ship, anti-submarine and anti-boat missiles -aircraft missiles and torpedoes for surface ships and submarines” and more.

Mr. Putin is unruffled by Western concerns about nuclear weapons. He sees his arsenal as an asset he can use to force the West to back down, and he is willing to take risks Western leaders would not take. Take the scenario that our collaborator Matthew Kroenig outlined on these pages in 2018.

Russia invades Estonia. “The US comes to the defense of its NATO ally, but while American troops advance, Russia deploys a tactical nuclear weapon on a US carrier group in the Baltic Sea, killing a few thousand. If you were President, how would you react?” It’s about forcing NATO to choose between all-out nuclear war or surrender.

NATO relies on gravitational bombs stored across Europe to deter this behavior or, if necessary, to react. But to deliver these tactical nuclear weapons to their target, NATO pilots must penetrate sophisticated air defenses. The risk of being shot down is great. The US recently deployed a low-yield nuclear weapon on ballistic missile submarines, but America only has about a dozen of these submarines.

Enter the SLCM-N, which would be less of an escalation than reaching for the ballistic submarines and could strike much faster than calling in strategic bombers. The Trump administration proposed the SLCM-N in 2018. Message to Mr. Putin: If you drop a nuclear bomb on NATO soil, the Alliance has the will and ability to respond in kind. This reduces the risk of Mr. Putin using a nuclear bomb.

This is not a novel weapon and does not negate US treaty obligations. The US Navy had a nuclear-tipped Tomahawk missile during the Cold War, which President Obama withdrew in 2010. The SLCM-N could serve as a deterrent without procuring large quantities or using it on every attack submarine.

It would also be useful to dissuade China from using a nuke on Taiwan without the prolonged and tense debate of, say, placing American nuclear weapons on Japanese soil. Which brings us to another point: If allies believe the US cannot or will not respond if attacked by Russia or North Korea or anyone else, they will develop their own nuclear deterrent. The SLCM-N could reduce the proliferation in an inconsistent moment.

The Trump administration said the US could reconsider the SLCM-N if “Russia returns to honoring its arms control commitments, reduces its non-strategic nuclear arsenal, and corrects its other destabilizing behaviors.” How does that go? Now, Mr. Biden is abandoning that leverage — likely to placate progressives who oppose nuclear weapons as an article of faith.

Several U.S. flag officers have told Congress they believe the country needs the missile, and this leadership’s openness is remarkable. The head of the US Strategic Command has warned of a “deterrence and security gap”. Joint Chiefs Chairman Gen. Mark Milley said he thinks “this president, or every president, deserves to have multiple options for dealing with national security situations.” Good advice.

Many in Congress want to reintroduce the SLCM-N into the military budget, and we hope they can do that. Nuclear weapons are a grim reality of modern life, but they are more likely to be used when adversaries believe the US and NATO lack an adequate nuclear deterrent.