The LRSO: It’s Time for Arms Control


The Pentagon’s plans to acquire a new nuclear air-launched cruise missile (ALCM), known so far as the Long-Range Standoff Weapon (LRSO), remain live. On 16th June, the House of Representatives rejected an amendment to reduce funding for the development of the LRSO. If adopted, the cut would have slowed the development of the new weapon by three years, perhaps buying enough time to reconsider the wisdom behind the programme. The vote (159-261) was largely bipartisan, with almost all Republicans supporting the existing LRSO timetable, and more than a third of the chamber opposing a weapon the Pentagon portrays as fundamental to US defence.

It is widely recognised in both legislative and executive branches that serious defence budget constraints loom on the horizon, illustrated by Secretary of Defence Ash Carter’s proposal for a separate nuclear modernization fund to shield future investment on nuclear weapons. But it may not be financial scarcity that kills the programme, rather than broader arms control considerations and question marks over whether the LRSO advances US national interests.

‘If you want peace, prepare for war’ is an ancient adage in-line with deterrence thinking. But strategies can easily become hostage of the weapons acquired to back them up; a particular danger when considering nuclear weapons. Acquisition decisions need to account honestly for its contribution to preventing (nuclear) war, its costs and the scale of destruction were it ever to be used. All this might be boiled down to an overarching question: does the weapon increase deterrence in any meaningful way? The LRSO does not fare well against this question. Its advocates seem to follow the rather simplistic argument that, in an uncertain and dangerous world, more nuclear weapons give the President more options; that more deter more effectively, and that less is more dangerous.

Firstly, the LRSO is marketed as an indispensable replacement of the current nuclear ALCM (AGM-86b) which must be acquired in order to maintain a viable air leg of the nuclear triad. LRSO advocates consider that without this weapon the strategic bomber fleet would be useless in the event the US needs to respond to an all-out nuclear attack. They consider that the stand-off capability of nuclear cruise missiles allows both deep penetration into enemy territory and the ability to destroy air defences in order to allow bombers to safely deliver gravity bombs. When the AGM-86b ends its service life, their argument goes, the LRSO will be necessary to retain this capability.

The US is also developing an advanced stealthy conventional air launched cruise missile (the JASSM-ER), which, like the Navy’s Tomahawk Block IV sea-launched cruise missile, will be capable of hitting targets with a level of accuracy that makes a nuclear blast unnecessary to destroy air defences or other A2/AD systems. In addition, the fact that the US could deliver nuclear deterrence with fewer nuclear warheads should not be a reason of concern. Under New START limits, if the US keeps fielding a fleet of 60 strategic nuclear bombers as it plans to do, it will in addition still be able to deploy the 1490 warheads deployed atop ICBMs and SLBMs. If Russia is not deterred by such a force, it is unlikely that the extra 600 warheads the LRSO would be able to deliver would make an appreciable difference. It is an illusion to think there is a fixed number of targets a state must threaten to deliver a credible nuclear deterrence.

Secondly, the LRSO is seen by its proponents as a useful tool to fight (and win) a limited nuclear war. Regardless if it is done as a reaction to Russian doctrines of limited use of nuclear weapons, to plan for nuclear warfighting (as opposed to effective deterrence) is a throwback to darker and more dangerous times. It was the planning for nuclear war devoid of any sense of political proportion which led president Reagan to conclude that a ‘nuclear war cannot be won and might never be fought’ and start working with the Soviet Union to stop the arms race. This same line of thinking inspires Democratic senator Dianne Feinstein, an outspoken opponent of the LRSO, who finds that ‘the so-called improvements to this weapon [in part reference to the variable-yield warhead the LRSO would be mated with] seemed to be designed candidly to make it more usable, to help us fight and win a limited nuclear war’. Hers and others’ concerns are understandable: after the nuclear taboo is broken, it is uncertain escalation can ever be controlled, and even a limited exchange of even small nuclear detonations would have catastrophic effects. In any case, the B61-12 on a stealth bomber is surely sufficient, making the LRSO redundant.

Thirdly, the LRSO is inextricably linked to extended deterrence and alliance assurance. LRSO supporters claim that the LRSO is necessary to reassure allies in response to Russia’s recent acquisition of advanced nuclear-capable cruise missiles, as well as its violation of the INF Treaty. But allies have no interest in the LRSO; indeed, it seems to be a source of concern. East European allies seek deterrence and assurance through greater conventional means and are lobbying for more commitment in that direction at July’s NATO Warsaw Summit. some see clear opportunity costs between the two options: ‘the money proposed on the LRSO could fund the rotation of an additional Armored Brigade Combat Team at a minimum, and leave room for a possible third or (perhaps more critically) additional enablers such as fire support assets, reconnaissance platforms or air defense systems to counter local conventional Russian fire superiority’.

NATO’s nuclear consultation mechanisms requiring unanimous approval of the LRSO deployment could prove problematic given its controversial status. Additional controversy could be triggered given the already strained nature of the nuclear nonproliferation and disarmament regime.

This new ALCM is not needed to bolster US nuclear deterrence and found be deeply controversial; it is an expensive and dangerous weapon which will not advance the US national interests. Washington might feel tempted to keep its acquisition plans in order to seek future Russian agreement on bilateral limitations and eventual elimination of nuclear cruise missiles, but this approach would be wasteful and could complicate future nuclear arms reductions, given the different role nuclear cruise missiles have in Russian nuclear strategy. The LRSO could be shelved unilaterally. The US acted unilaterally in 1991 when, through the Presidential Nuclear Initiative, President Bush started to withdraw the nuclear Tomahawk SLCM (TLAM-N). The TLAM-N genie was put back in the bottle for good; the LRSO genie does not even need to leave its bottle.

These are the views of the author.

Image: Boeing AGM-86B (ALCM), Source: USAF Museum

About the author(s)...
  • Alberto Perez Vadillo, EU Non-Proliferation Consortium Researcher worked with BASIC as a EU Non-Proliferation Consortium research intern.
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