The US’ Nuclear Posture Review, to be published early next year, will make decisions on modernising the US nuclear arsenal that could impact on systems operational until the end of the century. Speculation abounds, and many fear the the NPR could expand the size and remit of nuclear operations. It was reported that Congress and US allies were briefed this September on its progress. According to Julian Borger of The Guardian, the NPR is considering:
- developing a new low-yield warhead for a ballistic missile, possibly as a variant to the Trident D5 missile;
- reinstating the nuclear Tomahawk sea-launched cruise missiles;
- reducing the time needed for the US to resume nuclear testing from current levels of three years; and
- scrapping the US' pledge to only use nuclear weapons 'in extreme circumstances to defend the vital interests of the United States or its allies and partners,' and negative security assurances to never use nuclear weapons against non-nuclear weapon states in compliance with their NPT obligations.
President Trump has already shown a proclivity to endanger arms control agreements that affect Europe. His approach to the Iran Deal, negotiations with Russia on New START and a successor treaty and response the INF Treaty have revealed a rift between the US and European allies and the precariousness of European security. So, what could these additional changes mean for security in Europe and with Russia?
That the US is considering deploying new low-yield warheads is more of a confirmation than a revelation. Earlier this year, Air Force Chief of Staff David Goldfein stated he ‘absolutely’ wanted to have a ‘discussion about munitions’ and ‘yields’ in the forthcoming NPR, and Vice Admiral Robert R. Monroe recommended nuclear testing of ‘advanced and specialized warheads’ for ‘new-design’ weapons.
While low-yield weapons have often been debated in the US nuclear community – for instance, President George W. Bush’s planned ‘bunker buster’ bombs in the 2002 NPR – there is a notable difference in this debate: the potential target. In previous debates, counterproliferation has been the implicit aim. In September, General Selva, leading the review process, said that smaller yield nuclear weapons would give the President more options for using nuclear weapons in warfighting scenarios. Selva contends that the US needs a distinct nuclear capability for various tactical scenarios, ‘as horrible as nuclear war is, we do still apply some of the rules of war to it. So, a proportional reaction to an enemy's attack is actually a righteous and reasonable thing to do.’
Such comments give credence to the claim that the principal change of this NPR will be its aim at Russia, as the only country the US could conceivably fight a nuclear war with. In March, General Selva commented that the single greatest challenge facing the US arsenal since the last NPR in 2010 was the reemergence of Russia as a threat. Previously the two countries with over 90% of the world's nuclear weapons were seen as ‘no longer adversaries.’
Yet smaller yields tend to make weapons appear more usable, as they would likely cause relatively fewer indiscriminate civilian casualties compared to larger yield weapons. Combined with the ‘superfuze’ – which has radically improved warhead accuracy and efficacy, by allowing it to detonate early or late for maximum impact upon a hardened target, and which was introduced onto the Trident D5 warhead in 2009 – the US is far more capable of holding military targets, vital infrastructure and command and control centres at hostage with nuclear weapons than the Russia is. For Russia, this could be seen as undermining strategic stability and could provoke an increased reliance on tactical nuclear weapons or new nuclear developments.
The sea-launched nuclear-tipped Tomahawk cruise missile could similarly be perceived to undermine strategic stability. Nuclear Tomahawks, originally a land-based cruise missile, were removed from service in 1991 and dismantled in 2013. The view was that turning Tomahawk cruise missiles into purely conventional assets would reassure potential adversaries and allow them to be used in more conventional military situations without dangerous ambiguity.
The Trump administration has been searching for ways to respond to the alleged Russian violation of the INF since February. That the the NPR is considering sea-launched nuclear cruise missiles on top of accelerating the air-launched nuclear cruise missile programme, indicates a tit-for-tat and raise approach to diplomacy. In line with President Trump’s rhetoric, Russian nuclear developments will be met with more capable US developments without recourse to diplomacy.
A perennial issue for all dual-capable missiles and platforms, the reintroduction of nuclear-tipped Tomahawks could drive major crisis instabilities. It is not difficult to imagine how an escalating crisis could ‘go nuclear’ as Russia struggled to identify whether an incoming cruise missile was conventional or nuclear. Nuclear Tomahawks, like the D5 modification, would make nuclear weapons more usable, because of its accuracy and lower yield. This undermines what one may call strategic nuclear deterrence, promoting the idea that it could be acceptable to use nuclear weapons on a sub-strategic level to ‘restore’ strategic deterrence.
Most worryingly, the development of nuclear-tipped cruise missiles could legitimise Russian protestations that NATO MK-41 ballistic missile defence launchers in Romania or Poland, which were originally designed to to fire Tomahawk missiles, could be used to launch offensive nuclear missiles at Russia.
If these systems come to fruition, Russia will likely feel its security is undermined. This October, on the topic of new Russian air-launched and sea-launched cruise missiles, the INF Treaty and encroaching US systems, Putin said,
‘We believe that we have only balanced out the situation. If someone does not like it and wishes to withdraw from the [INF] treaty, for example, our American partners, our response would be immediate, I would like to repeat this warning. Immediate and reciprocal.’
The corollary of the US desire to build new nuclear weapons for new warfighting scenarios is the want to perhaps restart nuclear testing. The US has maintained an independent moratorium on nuclear testing since 1992, although it has not ratified the Comprehensive Test Ban Treaty. Yet, nuclear deterrence is slippery thing. If the US came believed nuclear deterrence encompassed warfighting and sub-strategic scenarios, then the US may justify future testing.
If the NPR scraps the US pledge to only use nuclear weapons ‘in extreme circumstances to defend the vital interests of the United States or its allies and partners’, and not to use nuclear weapons against non-nuclear-armed states, then clearly the US is considering new scenarios for nuclear use. This would mark a major step back from the broad consensus that nuclear weapons are for last resort. It also contradicts the current role of nuclear weapons within NATO. Both nuclear and non-nuclear-armed states will legitimately feel a renewed threat from US nuclear weapons, and may further question the United States’ commitment to a world free of nuclear weapons.
If the NPR delivers as reports suggest it will, it will likely become all the harder for those in the arms control community to improve security relations with Russia in Europe. The NPR may come to be seen as designed not to restore trust with Russia and improve global strategic stability, but to maximise US capabilities and freedom of action. Putin recently lamented, ‘we cannot do everything alone,’ in reference to the US’ unwillingness to seriously discuss the implications of strategic weapon systems in Europe. The fear is that the US will seek to go it alone in creating new nukes for radically new missions. In doing so it could bring new nuclear insecurities onto a continent that knows more than most the dire risks of security competition.