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BOOK REVIEW: Why More Warheads Bring Less Security
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September 2016

Reviewed by James E. Doyle

The Lure & Pitfalls of MIRVs: From the First to the Second Nuclear Age
Edited by Michael Krepon, Travis Wheeler, and Shane Mason, Stimson Center, 2016, 204 pp.

Embracing theories of nuclear war-fighting and deploying capabilities to attack the nuclear forces of a potential adversary provide nations with little security advantage and obligate them to spend vast defense resources on nuclear forces for decades. Such reliance on this expansive approach to nuclear deterrence can also hinder the improvement of political relations and increase the chances of unintended nuclear war during a crisis. China, India, and Pakistan should be mindful of this as they structure their future nuclear forces. Further, the security interests of the two dominant nuclear-weapon powers, the United States and Russia, would be served by disavowing theories of victory in nuclear warfare. 

That is the basic message of “The Lure & Pitfalls of MIRVs: From the First to the Second Nuclear Age,” an important recent study edited by Michael Krepon, Travis Wheeler, and Shane Mason and published by the Stimson Center. This study fills a gap and breaks new ground in the scholarship on the technology of the nuclear arms competition.

The focus of this collection of six essays is the technology for placing multiple nuclear warheads on a single ballistic missile and providing those warheads the ability to attack the protected nuclear forces of an adversary. Russia, the United Kingdom, France, and China have adopted this innovation, pioneered by the United States in the 1960s. India and Pakistan are developing this capability and are likely to deploy such missiles in the near future. 

This report makes a vital contribution to international security research and provides detailed history of the U.S.-Soviet rivalry in multiple independently targetable re-entry vehicles (MIRVs). Through the writings of regional security experts and former military officials, it also analyzes the emerging nuclear forces and doctrines in China, India, and Pakistan.

The study cautions decision-makers in China, India, and Pakistan that if they wish to “avoid repeating the missteps of the United States and the Soviet Union during the first nuclear age,” they must limit the extent to which multiple warheads are placed atop missiles and proceed at a slow pace. Most importantly, they should reject nuclear counterforce targeting strategies and war-fighting doctrine. Such nuclear war-fighting strategies during the first nuclear age resulted in heightened insecurity and a prolonged nuclear arms race.

The advent of MIRVs combined with increases in missile accuracy enabled the targeting of opponents’ nuclear forces by means of prompt hard-target-kill capabilities. The authors correctly conclude that “when deterrence of nuclear attack is predicated on the ability to attack opposing forces quickly, it becomes very hard for national leaders to stabilize political relations and proceed with arms control.”

MIRVs propelled vertical proliferation more than any other technological advance during the first nuclear age and gave rise to pyrrhic notions of prevailing in a nuclear war. This lesson is drawn from the solid research on the U.S.-Soviet nuclear arms race of the 1960s, ‘70s, and ‘80s. This study comes at a critical time because the United States and Russia are entering a new round of this competition and other nuclear powers appear to be following suit.

Perceived Advantages

MIRV technology combined with greater missile accuracy enables ballistic missiles to target hardened missile silos, airfields, submarine bases, and command centers. For example, the United States and the Soviet Union placed up to 10 or more nuclear warheads on a single missile so that a force of 50 missiles could destroy 500 or more separate targets. The United States made extensive deployments of MIRVs first, rapidly expanding the number of nuclear warheads in its arsenal. This was considered to have several important advantages. 

Most importantly, it was thought to provide a nuclear force superior to the Soviet Union. Although deterrence theory holds that nuclear war will be avoided because each side is equally vulnerable to destruction by the other, neither the United States nor the Soviet Union (or Russia today) has been satisfied with this condition. Each side sought nuclear forces that would provide some measure of advantage over the other. The United States, in particular, believed during the Cold War that the perception of nuclear superiority was vital to its entire national security and foreign policy strategies, as this study demonstrates with meticulous evidence from official documents, memoirs, and declassified sources.

This refusal to accept mutual vulnerability was expressed in many ways and drove the development of expanded nuclear doctrine and nuclear forces with ever-increasing capabilities. As Brendan Rittenhouse Green and Austin Long explain in the book’s first essay, “The Geopolitical Origins of US Hard-Target-Kill Counterforce Capabilities and MIRVs,” U.S. “[p]olicymakers believed that the nuclear balance would shape the political choices of other states—the Soviet Union, NATO allies, and third parties.... American leaders also believed that perceptions of the strategic balance abroad might influence international politics to the detriment of US national and international security.”

International Perceptions

Because U.S. policymakers believed that international perceptions of the balance were of pivotal importance for U.S. interests, they supported superiority in MIRVs and other measures of nuclear competition. It was considered essential that U.S. nuclear forces conveyed military strength and political resolve in order to reassure friends and induce caution among potential adversaries. Arcane metrics for assessing the nuclear balance such as missile payload weight, the number of deliverable warheads, their ability to defeat missile defenses, and their explosive power were valued and painstakingly assessed by strategic analysts. 

It did not matter that asymmetries in these categories of nuclear strength had dubious efficacy on the outcome of war if deterrence failed and a major exchange of nuclear weapons occurred. The perception of advantage was thought to be more important than actual advantage. This belief system sets up an endless cycle of nuclear weapons competition that endures and is intensifying between the United States and Russia today. 

The authors drive this point home with quotes from key U.S. statesmen of the Cold War era. For example, President Richard Nixon said of the nuclear balance, “Our view of our advantages or disadvantages will determine whether we can pursue an aggressive or timid foreign policy.”

James Schlesinger, U.S. secretary of defense from 1973 to 1975, argued that the United States might need large numbers of MIRVs with hard-target-kill capabilities “[j]ust so they [the Soviets] don’t think they are ahead.” Henry Kissinger, who served as Nixon’s secretary of state and national security adviser, also acknowledged that nuclear perceptions could be decisive. “Our [Strategic Arms Limitation Talks II] agreement can’t result in serious inequalities,” he argued, “if for no other reason than that other countries will look at these differences and assume we are inferior. Therefore, it will affect our foreign policy.” Stansfield Turner, CIA director from 1977 to 1981, also warned of the political consequences of letting the Soviets have a nuclear force that could attack U.S. land-based missiles and still have weapons in reserve: “I personally do not believe that [increasing U.S. missile vulnerability] means that the Soviets would be likely to be tempted to launch a strategic attack against us…. But I do believe that the perception of superiority that will give to the Soviets, and perhaps to our allies and others, is unacceptable to us.”

MIRV technology was also thought to provide the United States with several nuclear war-fighting advantages should deterrence fail. The first was so-called damage-limitation capability. The best way to limit an adversary’s ability to inflict damage on the United States was to promptly destroy as much of that nation’s nuclear arsenal as possible before it could be used. MIRVs allow an adversary’s nuclear arsenal to be heavily damaged by only a portion of an attacker’s overall force, leaving the attacker a potentially larger reserve of nuclear weapons to deter a weakened response. In the case of the Soviet Union, which deployed the vast majority of its nuclear forces on vulnerable silo-based missiles, this doctrine permitted one U.S. theory of victory in nuclear war. Following warning of an attack or pre-emptively, the United States could destroy much of the Soviet arsenal and national infrastructure and face only limited retaliation or possibly even termination of the conflict on favorable terms.

Of course, this theory also worked in reverse. Once the Soviets acquired a large force of intercontinental ballistic missiles (ICBMs) with MIRV capability, they too had the option to strike first. When both nations possessed such capabilities, the incentives to launch on warning of an attack increased. Because early-warning systems are imperfect and prone to false alarms, this raised the risks of nuclear war by accident or miscalculation, a situation that persists today. 

An undated U.S. Air Force photograph of LGM-118A Peacekeeper intercontinental ballistic missile re-entry vehicles during a flight test. The 50 deployed Peacekeepers, the most powerful U.S. missile from 1986 to 2005, were deactivated following the second Strategic Arms Reduction Treaty between the United States and Russia. [Photo credit: U.S. Air Force]Another military advantage offered by MIRV technology was the ability to implement limited nuclear strikes over a protracted period of time. U.S. strategists embraced such limited nuclear options as a plausible alternative to a massive exchange of nuclear weapons. Green and Long explain that these were conceptualized as attacks “with a limited number of weapons to cause pain, demonstrate US resolve, and incentivize the Soviet Union to stand down in the early stages of a nuclear war.” They quote a 1973 U.S. National Security Memorandum that asserts that limited nuclear options “could potentially also provide a capability to conduct discrete limited attacks on enemy forces in an immediate area to deny a local objective.” The cost-effectiveness of MIRVs, where one missile can carry several warheads, made acquiring these capabilities more feasible and provided wider targeting options.

MIRVs made another theory of nuclear victory possible. This was a limited pre-emptive strike designed to “decapitate” the Soviet command-and-control system and its most vulnerable nuclear forces, thus preventing it from marshaling even a ragged, weak retaliation. Targets to be struck by the fastest-arriving U.S. weapons (missiles with MIRV capability on submarines near the Soviet borders) included the Soviet political and military leadership, launch control centers and communications links, missile fields, and submarine pens. This threat from U.S. forces eventually led the Soviets to deploy a system called “perimeter” or “dead hand,” which could be predelegated to automatically launch nuclear retaliation against the United States without requiring authorization from the Soviet command authority, most or all of whom would have died in the U.S. attack.1

Hardened Targets

The embrace of nuclear war-fighting concepts such as damage-limiting first strikes, limited nuclear options, and decapitation all required accurate MIRVs capable of destroying hard targets because most militarily critical targets, including missile silos and command bunkers, were hardened to survive nuclear strikes that did not land very close to their aimpoints. When the capability to place the target within the crater caused by the nuclear explosion was acquired, these strategies became possible. 

Ironically, as the authors point out, “the strongest advocates of MIRVing in the United States and the Soviet Union were the quickest to question the motives behind each other’s programs: Why go to such lengths—and to the high launch-readiness associated with vulnerable and lucrative targets—if not to signal a commitment to nuclear warfighting in the event of a breakdown in deterrence?”

This key observation leads to another negative consequence of nuclear counterforce strategies, which is highlighted in the report’s second chapter, “The Impact of MIRVs and Counterforce Targeting on the US-Soviet Relationship,” by Russian scholars Alexey Arbatov, a member of the Scientific Council of the Russian Ministry of Foreign Affairs and the Advisory Council of the Russian Prime Minister, and retired Major General Vladimir Dvorkin, who had served as an expert for the preparation of key U.S.-Russian bilateral nuclear treaties.

That consequence is mutual misperception, fear, and distrust in military relations that spills over to the political dimension. Arbatov and Dvorkin convincingly argue that had diplomatic efforts to constrain MIRVs succeeded in the late 1960s and early 1970s, the U.S.-Soviet nuclear rivalry would have been far less intense and dangerous. The authors rightly contend, “The interaction of ballistic missiles and MIRVs with strategic doctrines of the United States and the Soviet Union deeply affected the military relations of the two powers for at least a quarter-century and precipitated two rounds of a highly expensive and threatening arms race—with dire implications for international security.”

The dynamics of the U.S.-Soviet arms race were clear: the deployment of accurate ballistic missiles with MIRV capability gave the United States the theoretical ability to deliver a disarming strike against Soviet strategic nuclear forces. 

The Soviet Union responded by deploying MIRVed ballistic missiles of its own to achieve parity in the number of warheads and to increase its ability to penetrate the anti-ballistic missile system that the United States was expected to develop. This development placed at risk the United States’ silo-based missiles and command centers. The United States then hardened its command and control and MIRVed hundreds of ballistic missiles aboard submarines that were relatively invulnerable to a first strike. The Soviets then deployed missiles on mobile launchers; created mobile command centers; built reserve airfields for its strategic bombers; and increased the number of nuclear ballistic missile submarines on sea patrol.

Both sides failed to acknowledge that some of the characteristics and capabilities of these weapons systems constrained options and compressed the timescale for decisions in a crisis, outcomes that made war by miscalculation more likely. Assessing the impact of force postures on war probability was not a priority for either side until after the Cold War was over. Unfortunately, it appears that the lessons of this history remain unlearned and classic nuclear stability is again taking a back seat to U.S.-Russian nuclear muscle-flexing, especially in the realm of nonstrategic nuclear forces. Indeed, the current controversy over launch-on-warning strategies that allow a U.S. president only several minutes to decide to retaliate for an attack indicated by error-prone early-warning systems is a legacy of the U.S.-Soviet competition in MIRVs.2

The U.S.-Chinese strategic relationship now equals or exceeds that with Russia in terms of its consequences for international stability. Beijing maintains strategic capabilities far below those of Washington and Moscow, but is modernizing its nuclear forces and appears to have equipped its DF-5 ICBM with MIRVs. As author Jeffrey Lewis makes clear, there is little evidence “to conclude that this is driven by military requirements associated with the pursuit of a counterforce targeting strategy.” Rather, the primary reason for China placing MIRVs on the DF-5 is to ensure that some warheads could penetrate U.S. missile defenses, therefore deterring U.S. aggression.

As Lewis makes clear, the chances that nuclear war-fighting strategies will enter the U.S.-Chinese strategic balance are growing. China has deployed anti-satellite weapons on the ground and in space that could eliminate the surveillance and intelligence on which the United States depends to attack mobile targets and cue missile defense systems. These systems would be lucrative targets for the United States in any future regional conflict with China and could be attacked early with long-range conventional weapons. 

The MK-21 multiple independently targetable re-entry vehicles for the LGM-118A Peacekeeper missile on display at the National Museum of the U.S. Air Force at Wright-Patterson Air Force Base, near Dayton, Ohio. [Photo credit: U.S. Air Force]The recessed nature of the Chinese nuclear deterrent might also increase classic forms of deterrence instability. Most Chinese warheads that can reach the United States are deployed on mobile missiles that remain in their garrisons and increasingly on submarines that spend most of their time in port. In this configuration, they are vulnerable to a first strike by U.S. MIRVs. Lewis observes that if both sides judged that war was about to break out, incentives would be high for China to disperse its nuclear forces and for the United States to strike them before this could be achieved. Moreover, Chinese strategists are beginning to highlight the potential benefits of alerting their nuclear forces to signal resolve and avoid nuclear coercion by the United States. The United States might perceive such alerts as preparation for launch and consider pre-emptive attacks, sharply increasing crisis instability.

MIRV technology would also introduce instabilities to the Chinese-Indian and Indian-Pakistani nuclear balances. Most Indian strategists agree that any increase in China’s nuclear strength requires a response from India. India suspects China of developing ballistic missile defenses. If it does so, India would have greater incentives to use MIRVs on its ballistic missile force. Other incentives exist, such as cost-effectiveness and the desire for India to be seen as possessing a technologically “modern” nuclear force. In fact, authors Rajesh Basrur and Jaganath Sankaran posit in their essay “India’s Slow and Unstoppable Move to MIRV” that making use of MIRVs in India may not even require political approval “because it is not viewed as a new weapon system, but one that is an extension of an existing (missile) technology.”

MIRVs or multiple warheads without independent targeting capability are not seen in India as inconsistent with its recessed deterrence forces. They could be developed for ballistic missiles that remain in a low state of day-to-day readiness. India does not possess the tracking or command-and-control capabilities to support counterforce targeting today, but will develop such capabilities over time. 

Pakistani nuclear doctrine differs fundamentally from Chinese and Indian doctrines. Pakistan sees nuclear weapons and the option to use them first as necessary to offset conventional force disparities with India. So, India’s pursuit of MIRVs and missile defenses challenge the effectiveness of Pakistani strategic deterrent. If India introduces MIRVs, Pakistan is likely to do so as well. This is the conclusion by Feroz Khan and Mansoor Ahmed in their chapter. Other priorities for Pakistan would be to increase the survivability of its nuclear forces through completion of a triad of delivery vehicles, the deployment of nuclear cruise missiles, and improvements to command, control, surveillance and targeting.

China, India, and Pakistan remain well behind the Unites States and Russia in counterforce nuclear capabilities, and their doctrines currently reflect these limitations. Over time, however, this study warns that “[t]he cascading effects of competitive MIRVing, flowing from the United States (and Russia) to China to India and finally Pakistan, have created a multidimensional security dilemma that appears to be leading inexorably to a new and complex problem in Asian security.” This dynamic will increase incentives for arms races, increased alert postures, and greater counterforce targeting capability—outcomes that decrease strategic stability in East and South Asia.

This report counsels that such negative developments are not inevitable but will flow from deliberate choices made by Asian nuclear powers. So far, China has exercised the most nuclear restraint, including the very limited size of its nuclear forces, its lack of counterforce capability, and the recessed nature of Chinese nuclear doctrine. In stark contrast to beliefs in the West that robust nuclear forces and war-fighting doctrine are essential enablers of successful foreign policy, China’s rise in world affairs has hardly been hindered by its modest nuclear strategy. Indeed, China may provide an example of strategically wise management of nuclear policy and resources. Although controversy surrounds China’s ambitions in the South and East China seas, its actions there have not been linked to expansive nuclear deployments or doctrine. India has also taken a measured pace to enlarging its nuclear arsenal and maintains a retaliatory doctrine. 

Whether this restraint will endure has grave implications for global security and depends on many unpredictable factors worthy of constant analysis. “The Lure & Pitfalls of MIRVs: From the First to the Second Nuclear Age” is a powerful resource for scholars and policymakers concerned with these questions. Its global scope, as well as its intricate details of the technical and political dimensions of the U.S.-Soviet Cold War arms race, provides valuable reference material that is accessible, well organized, and well documented with primary sources. This book advances understanding of the dynamics of nuclear arms competitions, the forces that trap nations in endless counterforce strategies, and the burdens and dangers that result. 


1.   Aaron Stein, “Putin’s Dead Hand,” Arms Control Wonk, podcast audio, March 8, 2015, http://www.armscontrolwonk.com/archive/5263/putins-dead-hand/.

2.   Jeffrey Lewis, “Our Nuclear Procedures Are Crazier Than Trump,” Foreign Policy, August 5, 2016, http://foreignpolicy.com/2016/08/05/our-nuclear-procedures-are-crazier-than-trump/.

James E. Doyle is is an independent nuclear security specialist. He was a technical staff member at Los Alamos National Laboratory from 1997 to 2014.

Posted: September 1, 2016