Cruise Control: Why the U.S. Should Not Buy a New Nuclear Air-Launched Cruise Missile

March 21, 2016

For special access to experts and other members of the national security community, check out the new War on the Rocks membership.

The Obama administration’s fantastical plan to modernize the Cold War-era nuclear triad of land-based missiles, submarine-launched missiles, and long-range bombers is prompting an increasingly loud and much-needed debate in Washington and beyond about whether the effort is necessary and sustainable.

One of the most controversial pieces of this “all of the above” sustainment approach, which is projected to exceed $350 billion over the next decade, is the Air Force’s proposal to build a new fleet of roughly 1,000 nuclear-capable air-launched cruise missiles (ALCMs).

The Defense Department and supporters of replacing the nuclear ALCM in Congress and the think tank community argue that building a new missile is necessary to maintain an effective U.S. nuclear deterrent because the current missile is losing its ability to penetrate increasingly sophisticated air and missile defenses. These proponents also claim that retaining an ALCM option for the bomber leg of the triad provides the president with unique options to control escalation and respond proportionally to a limited nuclear attack. In other words, the new missiles would augment the ability of the U.S. military to fight a nuclear war.

In the halls of the Pentagon, where planners have spent decades justifying nuclear force levels that would make a hoarder seem frugal by comparison, these arguments have taken on an almost religious quality. Yet strip away the magical thinking that permeates so much of U.S. nuclear strategy and the case for a new ALCM is weak: it is redundant, recklessly expensive, and potentially destabilizing.


ALCMs, which are currently carried by the B-52H long-range bomber, are guided missiles that can attack targets at distances outside the range of air defense systems. They were developed at a time when America did not have stealth bombers and sought an additional nuclear system with which to deter and impose costs on the Soviet Union.

America’s lone remaining ALCM variant is the AGM-86B, with a range of 1,500-plus miles. Multiple life-extension programs have kept the missile, which was first fielded in 1982 with a planned service life of 10 years, in service for more than 30 years. The Air Force is planning to retain the missile until 2030.

The Air Force is developing the long-range standoff cruise missile (LRSO) to replace the existing ALCM. The new missile will be compatible with existing B-2 and B-52 bombers, as well as with the planned B-21 bomber. The first missile is slated for production by 2026. Including the refurbished warhead that would be carried by the missile, the new weapon system is currently estimated to cost roughly $20 to $30 billion to acquire.

The LRSO is not the first time the Pentagon has sought to upgrade its nuclear ALCM capabilities. During the early 1990s, the Air Force developed the Advanced Cruise Missile, describing it as a “subsonic, low-observable air-to-surface strategic nuclear missile with significant range, accuracy, and survivability improvements over the ALCM.”

However, after spending $6 billion to buy and operate roughly 450 missiles, the George W. Bush administration announced the retirement of the system in 2008 due to major performance and reliability issues. The Pentagon hopes that the same fate that befell the ACM will not befall the LRSO.

A redundant capability

While supporters of the LRSO cite anticipated improvements in the air defenses of potential adversaries as a reason to develop the new nuclear cruise missile, it is doubtful that any target the missile could hit could not also be destroyed by other U.S. nuclear weapons or conventional cruise missiles.

For starters, the LRSO weapon is just one element of the Air Force’s plan for the air-based leg of the triad.

The service is planning to spend over $100 billion to build 80 to 100 new stealthy penetrating strategic bombers. One of the top rationales for building a new bomber is to extend America’s air dominance in advanced air defense environments. In addition to carrying the LRSO, the new long-range strike bomber (B-21) will be armed with refurbished B61 mod 12 nuclear gravity bombs. Upgrading the B61 is expected to cost roughly $10 billion. The B-21 is scheduled to remain in service for 50 years while the B61 mod 12 is expected to last 20-30 years.

LRSO proponents respond to this point by arguing that future air defenses could jeopardize unchallenged U.S. bomber operations in certain theaters. Though supporters do not claim that the LRSO would be inherently more survivable than the B-21, they claim that the LRSO would increase the number of penetrating targets each bomber presents to an adversary. But in the event the B-21 can’t reach a target with a gravity bomb, the weapons associated with the other two legs of the nuclear triad, submarine-launched ballistic missiles (SLBMs) and intercontinental ballistic missiles (ICBMs), can penetrate air defenses and strike targets anywhere on the planet with high confidence.

Indeed, in making the case for the LRSO, supporters often ignore the other two legs of the triad altogether.

As if this wasn’t head-scratching enough, some sources say there are significant restrictions on the use of the existing ALCM due to aging and reliability issues. This raises yet another question: If the ALCM only serves a “back-up” role in the current U.S. nuclear war plan, how is it wise to invest $20 to $30 billion in a completely new system?

Meanwhile, the Air Force is significantly increasing the lethality of its conventionally armed cruise missiles.

For example, the service is purchasing thousands of stealthy precision air-to-surface standoff cruise missiles designed to attack targets from outside the range of adversary air defenses. Known as the JASSM-ER, the missile will have a range of roughly 500 miles and be integrated onto the B-1, B-52, B-2, F-15E, and F-16 aircraft — and likely on the F-35 and B-21 as well. The Air Force is also planning to arm the JASSM-ER with a new computer-killing electronic attack payload. The technology is designed to have an effect similar to an electromagnetic pulse. The Navy’s sea-launched Tomahawk cruise missile is also a highly capable and continually improving conventional standoff weapon, and it has an even longer range than the JASSM-ER.

Enhanced warfighting capabilities

Given there is nothing unique about the penetrating mission of a nuclear ALCM, devotees of the missile often emphasize other supposed attributes of the system, including that it would come in handy in potential scenarios involving limited nuclear escalation.

The idea here is that the weapon system, by virtue of the lower yield of the nuclear warhead it carries, provides the president with the ability to respond proportionally to a smaller-scale nuclear attack by an adversary, thereby enhancing the U.S. ability to deter such attacks from taking place and assuring allies that Washington will respond decisively to limited use.

Yet U.S. nuclear capabilities would remain highly credible and flexible even without a nuclear ALCM. The arsenal includes other weapons that can produce more “limited” effects, most notably the B61 gravity bomb. More importantly, the notion the use of nuclear weapons can be fine-tuned to carefully control escalation to a full-scale nuclear exchange is very dangerous thinking. It is highly unlikely that an adversary on the receiving end of a U.S. nuclear strike would (or could) distinguish between a large warhead and a small warhead. The fog of war is thick. The fog of nuclear war would be even thicker.

Large or small, nuclear weapons are extremely blunt instruments, both in terms of their destructive power and the taboo associated with the fact they have not been used in 70 years. As Michael Krepon has elegantly put it, the case for the LRSO “demands a fealty to nuclear warfighting concepts that most Americans will be hard-pressed to understand. The nuclear deterrence business is most persuasive to taxpayers in the abstract; particulars require the suspension of disbelief.”

Other arguments in favor of the LRSO are also unconvincing. The Defense and State Departments claim that strategic bombers armed with ALCMs and gravity bombs are more “stabilizing” than the capabilities inherent in the other legs of the triad because the airborne leg provides a nuclear response option that is observable and does not pose the threat of a disarming surprise attack. Yet a B-21 bomber armed with the LRSO will be more difficult to detect than the current B-52/AGM-86B arrangement, and may not always be observable or provide more potential for warning, especially in a crisis. Indeed, some supporters of the LRSO emphasize its utility for achieving tactical surprise in combat.

The LRSO raises serious questions about stability that have yet to be fully explored. The new missile and its associated refurbished warhead could be vastly more capable than the current ALCM in terms of characteristics such as stealth, speed, range, accuracy, and yield variability. As noted above, the missiles will be deployed on the more advanced B-2 and B-21 bombers. In addition, some sources have said that the Pentagon is envisioning potential uses for the new cruise missile that go beyond “the original mission space” of the ALCM, namely in contingencies involving China.

Furthermore, as highlighted by William Perry, President Bill Clinton’s defense secretary, and Andrew Weber, President Barack Obama’s assistant secretary of defense for nuclear, “cruise missiles are a uniquely destabilizing type of weapon” due to the fact that “they can be launched without warning and come in both nuclear and conventional variants.”

The possible risk of miscalculation and unintended escalation posed by the LRSO requires far more scrutiny than the blithe assertions from the administration that the missile will be stabilizing.

Indefensible Costs

The case for the LRSO is further undermined when one considers the high budgetary costs and significant opportunity costs. The United States is planning to rebuild all three legs of the nuclear triad and their associated warheads at a cost and on a schedule that many military leaders say is unsustainable. As Todd Harrison, the director of defense budget analysis at the Center for Strategic and International Studies, convincingly demonstrates in a recent report, the cost to sustain the nuclear mission is scheduled to peak during the 2020s and overlap with heightened levels of projected spending on conventional weapon system modernization programs.

While no one knows for sure what the military budget will look like after the expiration of the Budget Control Act in 2021, it seems unlikely that there will be enough money to fund all of the military’s nuclear and conventional modernization proposals. This will force the U.S. government to choose between the nuclear effort and other military priorities. What’s more, the president and his military advisors have determined that the United States can reduce the size of its deployed strategic nuclear arsenal by up to one-third below the 2010 New Strategic Arms Reduction Treaty (New START) levels, Nonetheless, the proposed nuclear spending plans are based on maintaining the New START levels in perpetuity.

The bloated U.S. nuclear arsenal of approximately 4,700 weapons is largely irrelevant to the most pressing national security challenges the United States faces. Retaining an unnecessarily large arsenal and enhancing U.S. nuclear warfighting capabilities will not help Washington address the challenges posed by great powers such as Russia and China. If anything, doing so will exacerbate relations with these countries.

The choice is clear: chart a more realistic path for the nuclear arsenal that doesn’t severely constrain the force-sizing options of future presidents and reduces the risk of doing serious damage to conventional capabilities and other national security programs. As an early step in this course correction, the Pentagon should cancel its new cruise missile program and prioritize continued investments in the other legs of the nuclear triad and more relevant and usable non-nuclear capabilities, including longer-range conventional cruise missiles.

Doing so would be far more beneficial to U.S. security than spending billions to buy a redundant new nuclear missile unneeded for either deterrence or assurance.


Kingston Reif is the Director for Disarmament and Threat Reduction Policy at the Arms Control Association. You can follow him on Twitter at @KingstonAReif.


Image: USAF, Senior Airman Benjamin Gonsier

We have retired our comments section, but if you want to talk to other members of the natsec community about War on the Rocks articles, the War Hall is the place for you. Check out our membership at!

7 thoughts on “Cruise Control: Why the U.S. Should Not Buy a New Nuclear Air-Launched Cruise Missile

  1. The main issue with not developing a new cruise missile is threat asymmetry. The Russians and Chinese are developing such missiles, The fact is, the Russians and Chinese are taking the initiative in restarting the nuclear arms race, making a mockery of New START and nuclear arms control in general.

    The whole concept of negotiating strategic arms control with nations like Russia and China whose decision-making on whether to proceed in good faith with their acquisition of new strategic weapon systems has been flawed from the beginning. Soviet arms controllers were so locked out of that process that they had no data at all on their own nation’s nuclear arms capabilities during the SALT negotiations and had to essentially use information provided by the US side of the negotiation as a basis for negotiations. That these treaties are routinely violated by the closed societies we negotiate with was shown by former deputy director of the secret Soviet biological warfare production group Biopreparat Ken Alibek in his book Biohazard, which begins with Alibek’s account of having been called over to a night meeting with Gorbachev and directed to make weaponized biological agents available for placement in warheads aimed at the US and UK. There’s no downside for the current Russian and Chinese governments in cheating on arms control. So this article’s suggestion that the Russians and Chinese might react badly if we get new cruise missiles is grimly funny – they’re reacting badly NOW to our current arms control efforts with threats to detonate EMP weapons over North America (Russia) and devastate the the US West coast (China) and leaks of alleged salted nuclear weapons (Russia). Worry over whether people capable of making statements like this will be “infuriated” if we acquire a new weapons system is ludicrous. It’s another indication of the entirely alternate universe inhabited by believers in the value of strategic arms control.

    1. Your statement is ridiculous. In the late 70’s, the Soviet Union possessed an estimated 40,000 warheads. After the various SALT agreements and other treaties, the number of warheads dropped by over 80%. In addition, the Soviets unilaterally removed several categories of nuclear weapons simply to get the negotiations going, indicating their strong interest in reducing the amount of nukes everywhere. This wasn’t some humanitarian gesture, it was because nuclear weapons were and are ruinously expensive.

      For your assertion that Russia and China are fundamentally untrustworthy actors, remember that the United States has continuously pursued technologies to attempt to upset the nuclear equilibrium, including hypersonic conventional weapons, missile defense systems, and far out technologies like the YAL-1. This is especially threatening to Russia, which places a high value on its nuclear deterrent. It is even more provocative to China, which is the only country of the three to maintain a no-first use policy, and to have a minimum credible deterrent sensitive to increases in defense systems.

      There is never a situation, at least in today’s world, where the first use of nuclear weapons could be justified. If our current arsenal does not deter an adversary, there is nothing that could.

      If you want to actually make a deal, the more powerful of the two has to step forward. Russia is in financial free-fall, and would welcome the ability to direct nuclear spending into plugging the hole in welfare and pension spending, which the regime needs to maintain popular support. Besides, an arms control treaty would treat Russia as a great power, which would assauge Russia’s ego and allow them to claim victory in a deal that would vastly benefit us.
      China would accept nuclear reduction, for increases in their arsenal in an attempt to keep up with us is raising the possibility of an independent Japanese or South Korean program. Just like Russia, assauging their ego at the negotiating table is far easier than dealing with a revanchist war later on. In total, your ignorance of the benefits of negotiation is disturbing. Even Reagan wanted all nuclear weapons gone.

      1. Thomas, your own ignorance on what today’s Russia is also is disturbing. Otherwise you would have known that any negotiation with Russia must be conducted from the position of overwhelming power in order to have any type of success.
        Your arguments remind me vocal opponents of the economic sanctions currently imposed on Russia. If you don’t care what happens to EU and the world in the next 10-20 years yes, feel free to go back to business as usual with the Great Power of Russia.

        1. “Thomas, your own ignorance on what today’s Russia is also is disturbing. Otherwise you would have known that any negotiation with Russia must be conducted from the position of overwhelming power in order to have any type of success”.
          Comparatively, the United States is in a far stronger position than it ever was during the Cold War. Russia is barely reaching a level of capability it had in the late 80’s.
          In addition, the validity of that argument is suspect. We were unable to coerce the Soviet Union in the 50’s, when we possessed overwhelming nuclear superiority , but dealt with them in the 80’s, when their single-minded focus on their nuclear arsenal resulted in a substantially higher warhead count and clear margin of safety for any MAD situation.
          “Your arguments remind me vocal opponents of the economic sanctions currently imposed on Russia. If you don’t care what happens to EU and the world in the next 10-20 years yes, feel free to go back to business as usual with the Great Power of Russia.”

          The US sanctions are symbolic, and I don’t speak for Europe. I also know Russia is fundamentally weak and unstable, and another decade of low oil prices will send them back to the 90’s. Europe faces a host of problems, but Russia isn’t that high on the list, except for the Baltics. Instead of “flexible” nuclear weapons, wouldn’t encouraging our allies to take over the conventional roles and providing a nuclear umbrella be more cost effective, and restore some European dignity and respect in their armed forces?

      2. In response to your statements, the US walked square corners in its development of weapon systems. When we were ready to deploy antimissiles, we withdrew from the ABM treaty legally.

        In comparison, Gorbachev’s orders to Biopreparat to arm Soviet ICBMs with biological weapons directly and covertly contravened the Biological Weapons Convention.

        As a repository nation for that treaty, the USSR had one legal option there – do as we did, and withdraw (under Article XIII, section 2) giving three months’ notice in advance. The USSR did nothing of the sort, and kept its biological weapons effort AND, presumably, its capacity to strike the US and her allies with biological warheads on ICBMs until Biopreparat deputy directors Alibek and Pachesnik defected and revealed the program’s existence. Ken Alibek revealed Gorbachev’s orders to arm ICBMs with biological weapons in his book Biohazard. It wasn’t until after well after the fall of the Soviet Union that Russia officially stopped using Biopreparat’s vast research and bioweapon manufacturing empire (although their research applicable to creation of highly virulent virus strains continues).

        THAT is what I’m referring to. Russia has a long tradition of duplicity in the area of strategic arms control compliance. Their own ABM system exceeding the ABM Treaty’s stated limits (“Mozyr”) ( dates back to 1980, before Reagan’s “Star Wars” speech.

        Negotiation with Gorbachev got us biological weapons on ICBM warheads pointed at us, and more recently, Russian development of cruise missiles in direct violation of the INF treaty.

        Your ad hominem comments above don’t change the fact that negotiations with a closed society are basically worthless. We’ve declared the existence of all the weapons systems you refer to. We can only guess at what Russia and China have (apart from Russia’s claims for the performance of the PAK-FA fighter). It appears that mere treaties aren’t constraining the sorts of weapons they’re developing and deploying.

  2. It will continue because no one in the levels of industry, politics or military wants to see other superpowers with nuclear tipped cruise missiles or the US losing the arms race game. That’s the sad part of the US military procurement regime.

  3. This article unfortunately says nothing new from the disarmament community’s view on US nuclear weapons, but it deliberately distorts the military’s development of a needed capability for nuclear deterrence. Those who understand nuclear deterrence have been reduced to rabid planners who “make a hoarder seem frugal” with their nuclear funding demands, supporters and proponents of a weapon system rather than defense professionals within the DoD nuclear enterprise, “devotees” of the missile as if we were worshipers of a South Pacific cargo cult.

    Reif says that funding the Long-Range Standoff (LRSO) missile is “redundant, recklessly expensive, and potentially destabilizing.” These are old charges, none of which have stuck despite his constant repetition of charges. As is the case with every DoD weapon system, as one system ages, often DoD will develop a replacement system. In this case, the AGM-86B is due for replacement. As Reif notes, it’s been in the system for 30 years and will have to do for another 13-14 years. This is an old system. There was a replacement, the Advanced Cruise Missile, but there were operational problems and that system isn’t around. So given that the requirement is still valid, based on Joint Staff and OSD approvals, yes, DoD is going to try to develop a new cruise missile that is more capable than the old version. What a shock.

    Reif says that LRSO costs are “excessive.” He refuses to put the cost of this single weapons program in context with other defense programs or the defense budget in general, which is why CSBA notes that the cost of nuclear forces is in fact affordable. The nuclear weapons programs have to compete today with other defense programs – the funding, as approved by the Air Force and DoD, is not seen as excessive but rather necessary. Is it redundant because we also have a gravity bomb (B61 mod 12) that is used on bombers? The nuclear deterrence community don’t think so. Two reasons – first, the B61 mod 12 gravity bomb supports “nonstrategic nuclear weapons” stockpiles in Europe as well as providing a limited nuclear deterrent against small nuclear powers. Second, using a gravity bomb means you have to fly over the target. Even with “stealth bombers” (reminder, “stealth” does not mean “invisible”), we try to avoid flying over heavily defended, high-value targets. Using standoff capabilities is vastly preferred, given expected advances in Anti-Air/Area Denial (A2/AD) technologies.

    In addition, the next generation bomber may not be ready in the numbers required for nuclear deterrence and conventional missions in 2025, when the LRSO will be ready. There’s a gap of maybe 10-20 years in which the US military will have B52s continuing a nuclear role with advanced A2/AD threats. By deploying the LRSO on the B52, it can continue to play a valuable role in supporting the nuclear deterrent as the next gen bomber is developed. Reif continues his strawman by saying we nuclear advocates are “ignor[ing] the other two legs of the triad altogether.” And that’s just untrue. DoD counts on the triad to provide multiple, complementary capabilities to deny any adversary the comfort of thinking that a first-strike with nuclear weapons against the United States is ever possible. The one existential threat that could change the US government in a day does deserve some no kidding tough capabilities.

    This is all “head-scratching” hard mental work to Reif, but not to defense analysts. No one in the nuclear enterprise views cruise missiles as a “back-up” to the current US nuclear war plan, as he claims. It’s a vital component, providing options to the president for both near-peer nuclear powers as well as emerging nuclear powers. It isn’t as if this hasn’t been discussed within the JROC and OSD and the State Department. This is all within the New START treaty limitations and, what a surprise, both Russia and China are developing cruise missiles with nuclear warheads. So is this US cruise missile somehow more “destabililizing” than the Russian and Chinese variants? That’s hard to understand.

    Reif wants us to believe that conventional weapons such as the JASSM-ER and Tomahawk cruise missile should be included in the conversation. And certainly, the Nuclear Posture Reviews have emphasized “non-nuclear” capabilities to augment the nuclear mission. That doesn’t mean, however, that one can abandon capabilities for low-yield, highly accurate nuclear weapons. Strategic deterrence writ large will always include every military and political option, and in some cases, the US government will have to respond to a nuclear threat with a nuclear capability. Having both cruise missiles and gravity bombs that are nuclear capable are required for future military operations. No one outside of the disarmament community argues with this.

    Last, and I will get off the stage here, Reif ends this article with his favorite statement about the “bloated US nuclear arsenal of approximately 4700 weapons” as being “largely irrelevant to the most pressing national security challenges the United States faces.” Sorry, I thought Russia’s nuclear rearmament and its flying nuclear-capable bombers over Europe and off the West Coast of the United States might register as one of those “most pressing” challenges. And for the record, the US military doesn’t have 4700 nuclear weapons in an operationally-ready status. Many remain in reserve, awaiting eventual demilitarization. Staying within the New START treaty requirements and maintaining a credible nuclear deterrent requires new delivery systems such as the LRSO for the future operating environment.