By Matthew Harries, Managing Editor of Survival; Senior Fellow for Transatlantic Affairs and Nuclear Policy
The new US Nuclear Posture Review (NPR), released on Friday, contains troubling recommendations to broaden the role of nuclear weapons in American strategy, but omits more radical options that some observers had anticipated. Overall, it feels more swamp than Trump – that is, it gives the impression of having been written by informed professionals within the mainstream of US national-security thinking, albeit clearly at the hawkish end of that spectrum.
The NPR’s most eye-catching feature is the call for the United States to develop new nuclear capabilities to deter limited nuclear use by others. The NPR calls for a low-yield warhead on the existing Trident D-5 submarine-launched ballistic missile as an interim measure, and a new sea-launched nuclear cruise missile for the longer term.
The idea behind these new weapons is to solve an apparent deterrence problem that for the last few years has been keeping Western defence planners up at night. The problem is this: what happens if an enemy country, having started a conflict in its near abroad, uses the threat of limited nuclear use to get the US and its allies to back down? Worse, what if that country actually carries out a small-scale nuclear strike and threatens more of the same if the US chooses to fight on?
The enemy country in this scenario is usually Russia, and the conflict is typically a small to medium-scale war in a Baltic state. What worries some officials is the perception that the US cannot deter such threats because it lacks an equivalent capability to match Russia, which has clung onto many hundreds of short-range and low-yield nuclear weapons, and is busy developing and deploying short- and medium-range missiles capable of carrying conventional and nuclear warheads. US officials fear that they could be left with two bad options: either backing down and giving Russia the huge victory of a politically broken NATO, or escalating to mutually catastrophic strategic nuclear war.
The concern is not totally baseless. Russia has annexed a portion of a neighbouring country and continues to wage limited war against it. Russian President Vladimir Putin has repeatedly reminded the world of Russia’s nuclear potential. And Russia has in the past envisaged, in official policy, the possibility of limited nuclear use along roughly these lines, although in public doctrine published since 2010 it has not done so. It is by no means clear that Russian leaders are actively considering nuclear use as a way of ending a limited conventional conflict – but it is not impossible to imagine a crisis in which the thought might cross their mind.
But if the NPR's diagnosis is understandable, the prescription is deeply misguided. For one thing, the military rationale for new limited nuclear options is dubious. The US already has low-yield nuclear warheads that can be delivered on gravity bombs (including those hosted by NATO countries) and air-launched cruise missiles. There might be some added theoretical value of a sea-launched nuclear option in terms of its ability to get through Russian air defences, but not enough to justify the political and monetary costs. Those costs will no doubt be on Congress’s mind in deciding whether to green-light new nuclear capabilities – and whether or not anything gets built, American adversaries have been handed an easy talking point to justify their own nuclear upgrades.
More importantly, NATO’s deterrence task is primarily conventional, not nuclear. The Baltic states border Russia, not the United States, and they are an awfully long way from the bulk of NATO ground troops. Preventing Russia from successfully pulling off a limited incursion, and reinforcing front-line forces in a developing crisis or war, are grave and ongoing challenges that new nuclear weapons do little to address.
In any event, the toughest problem the US and NATO face is political, and well beyond the scope of the NPR’s mandate. Defence planners ultimately worry about the limited-war contingency because they fear that the West does not have the guts to risk a serious war with Russia in order to defend the eastern allies. This problem predates the Trump administration, but having a president who crudely derides US partners surely does not help. Proposing new nuclear weapons is perhaps a natural answer for nuclear-weapons specialists to offer – but it does not make for effective US strategy.
As a foreign observer, what I find most surprising about the call for new low-yield nuclear weapons is how nervous it shows the United States to be. If it is true that Russia’s supposed strategy is concerning, it is also true that for Russia to actually execute this strategy would be a thoroughly stupid idea. Does Russia really want to become the first country to use nuclear weapons since 1945, all for the sake of capturing a slice of the Baltics? Securing Crimea and spoiling Ukraine's Western shift was one thing – but risking an honest-to-God war with the United States just to prove that NATO's Article V is shaky?
Russia has attacked the foundations of post-Cold War order in Europe, and has provided shelter and comfort to a chemical-weapons user in the Middle East. Getting tough is not necessarily a bad idea. But Russia is a threat that a confident United States – vastly more powerful in economic and military terms – should be able to handle without recourse to new nuclear hardware. This NPR, along with the debate over preventive war with North Korea, suggests that the United States is not sure it can still deter weaker adversaries. Here’s hoping America holds its nerve.