U.S. Air Force maintenance crew members exit an ICBM nuclear missile silo near Malmstrom Air Force Base in Montana, August 2005
Adam Tanner / Reuters

Late in the afternoon of Sunday, February 27, Russian President Vladimir Putin convened a group of senior Kremlin officials to witness an extraordinary public statement. Putin announced that he had taken the “unprecedented” step of ordering Russia’s nuclear warheads to be prepared for “special combat readiness.” Between Putin’s nuclear saber rattling and growing anxiety over the prospect of a military conflict with China over Taiwan, once arcane questions of nuclear strategy and deterrence have returned to the center of world politics.

Not since the 1991 collapse of the Soviet Union has the fear of great-power nuclear conflict played such a central role in international affairs. The nuclear-strategy learning curve has been steep for many of the world’s policymakers and elected officials. Those old enough to remember Cold War–era nuclear debates are learning that the field has transformed and that the lessons and beliefs that once guided policy are rarely applicable today.

The unique challenges of the Cold War shaped strategic thinking about deploying nuclear weapons in particular ways. Today’s circumstances are quite different, and merely applying the lessons of the past would be wrong-headed and even dangerous. Unfortunately, much of the nuclear muscle memory in the United States—intellectual, strategic, and organizational—has its roots in a Cold War experience that sheds little light on our present and future nuclear challenges.

In particular, Washington should move away from the Cold War–era thinking that focused on preemptive postures and counterforce weapons designed for a massive strategic exchange. The United States should accept that it will probably never use nuclear weapons preemptively—or even at all—except in the unlikely event that the U.S. homeland is subject to a nuclear attack. Washington’s goals of extending deterrence and limiting nuclear proliferation could be better achieved if the United States and its allies enhanced military capabilities that are usable and effective during a conflict. Moreover, in the coming years, emerging technologies and a broad balance of conventional military power will have a far more significant impact on deterrence and defense outcomes than will nuclear weapons.

STRATEGY SHAPED BY WAR

At the start of the nuclear age, American strategic thinking was influenced by three decades of murderous global conflict that had pulled a reluctant United States into two world wars. World War II was driven by authoritarian states pursuing total war, two of which, Nazi Germany and imperial Japan, launched what were seen as surprise attacks in 1941: Germany’s invasion of the Soviet Union during Operation Barbarossa and Japan’s attack on Pearl Harbor. Based on this history, Washington assumed that the totalitarian Soviet Union similarly sought global conquest and might even launch a surprise attack on the United States—“a bolt from the blue” as it came to be known in the nuclear realm.

Another component of American thinking at the dawn of the nuclear era was the fact that the devastation wreaked by World War II, the weakening of traditional powers such as France and the United Kingdom, and the complete defeat of Nazi Germany and imperial Japan had created massive power vacuums. The United States was separated from these power vacuums by two oceans. The Soviet Union, on the other hand, had the world’s largest army—which it maintained through a command economy—and the benefit of proximity. If Moscow took advantage of this asymmetry to seize territory, it could build a Eurasian economic and industrial base that could present an existential threat to the United States.

That prospect caused the United States to break with its traditional avoidance of foreign entanglements and offer peacetime protection to far-flung allies and former adversaries.

Washington did not, however, have any reasonable, cost-effective means of defending them with conventional military forces, short of constructing a garrison state and potentially bankrupting its own economy. The other option—allowing vulnerable allies to acquire their own nuclear weapons to deter the Soviet Union—could restrict Washington’s freedom of action, expose it to emboldened regional actors, or entrap U.S. forces in avoidable conflicts. Allowing West Germany and Japan to possess nuclear weapons could destabilize Europe and Asia, fracturing efforts to build alliances and provoking Soviet intervention. For those reasons, nonproliferation became a core tenet of postwar U.S. grand strategy.

It is difficult to say whether U.S. Cold War nuclear strategy was ingenious or just lucky.

Furthering the strategic challenge, Europe would not recover economically—nor would it be possible to defend—without the recovery and participation of West Germany. Moscow and even Washington’s close European allies were understandably concerned about the rehabilitation of a divided country that had recently caused unimaginable death and destruction. For its part, West Germany was unenthusiastic about formalizing its second-class status and conceding its territory in a European war. Nor would Bonn embrace a military strategy that defeated the Soviet Union through a U.S. nuclear bombardment that left its territory an irradiated ruin. Similar calculations also affected Japan.

These circumstances shaped American thinking about nuclear weapons and the defense of Europe. If a war was imminent, U.S. strategy anticipated the massive and preemptive use of nuclear weapons to eliminate the Soviet Union’s nuclear capabilities while blunting its conventional superiority before Soviet troops crossed the intra-German border. This aggressive strategy would, it was hoped, dissuade allies, especially West Germany, from acquiring independent nuclear capabilities. Such a daunting task necessitated enormous quantities of weapons, delivered with accuracy, speed, and stealth, with the ability to target Moscow’s strategic assets before they were launched. These objectives were captured in the United States’ nuclear war plan, the Single Integrated Operational Plan (SIOP), developed in the late 1950s and revisited and updated throughout the Cold War.

It remained unclear, however, whether a nuclear strategy that called for the United States to threaten a global thermonuclear war in a crisis and expose its homeland to devastation was credible. And over time, a combination of factors made the idea of a president of the United States launching the SIOP increasingly implausible. In the 1960s, the Soviet Union achieved second-strike survivability, or the ability to visit unacceptable damage on the United States even after it had been attacked, and eventually strategic parity with the United States. A revolution in satellite-based surveillance technology calmed worries about a surprise attack. Concurrently, the shared fear of nuclear catastrophe, the costs and dangers of the nuclear arms race, the political appeal of arms control, and a mutual interest in stanching proliferation generated superpower cooperation to limit the risks of nuclear weapons.  

As a result, the contradictions in U.S. strategy ran deep. Washington sought strategic stability through arms control with Moscow based on mutual vulnerability and the removal of incentives for either side to use nuclear weapons first. But the United States simultaneously embraced strategies and weapons that sought an elusive nuclear advantage in order to extend deterrence, limit proliferation, and pressure the Soviet Union. The resulting strategy was expensive, contradictory, and lacked credibility. And yet arguably, it worked. Despite occasional disagreements, NATO partners and other allies accepted the strategy and cooperated. Nuclear proliferation remained constrained. And Washington’s efforts to achieve a nuclear advantage appeared to affect Soviet leaders, driving them into an expensive arms race that many analysts contend exposed the Soviet Union’s structural weaknesses and helped accelerate the process that eventually led to the dissolution of the Soviet Union. Looking back, it is difficult to say whether the United States and its nuclear strategy were ingenious or just lucky.

RISING COSTS OF CONQUEST

Although fraught and uncertain, the current international political environment does not rival the early Cold War in terms of danger. Neither China nor Russia is likely to dominate the Eurasian landmass the way the Soviet Union threatened to do in the middle of the twentieth century. Over time, the costs of conquest have risen dramatically, and the benefits have fallen. Instead of the exhausted, weak states that dotted the Soviet periphery, China and Russia are surrounded by a range of influential, economically vibrant countries possessing impressive military potential and strong ties to the United States. Moreover, Russia’s contemporary conventional capabilities have been exposed as overrated, and China’s remain untested. China has not responded with enthusiastic support, let alone cooperation, to Russia’s invasion of Ukraine. The United States can project impressive conventional military power relative to its adversaries better than it could during the Cold War. A surprise nuclear attack on the United States is improbable. Instead, contemporary China and Russia may use nuclear deterrence to prevent the United States from intervening in regional conflicts in their backyard.

Moreover, it has become increasingly difficult to imagine the United States using nuclear weapons to do anything but defend its homeland. It is hard, for example, to envision a U.S. president using nuclear weapons first, even if China invaded Taiwan or Russia overran Estonia. It is unrealistic to rely on a Cold War–era threat of strategic preemption to deter or defeat regional aggression by great-power adversaries.

For that reason, the relevance of the strategic nuclear balance between the great powers has diminished. Strategic nuclear superiority matters less in a world in which it is difficult to imagine the United States or another great power authorizing a preemptive first strike. China’s calculations toward Taiwan, for example, are unlikely to be decisively shaped by the United States’ significant strategic nuclear superiority. The balance, both quantitatively and qualitatively, of conventional military capabilities, especially those based on emerging technologies such as artificial intelligence, will shape strategic behavior far more than one side being better able than the other to limit damage or dominate the “escalation ladder” in a hypothetical strategic nuclear exchange.

Nevertheless, the primary goal of U.S. nuclear strategy should still be to maintain its secure second-strike survivability. Although a coordinated Chinese-Russian nuclear strategy, to say nothing of a combined nuclear attack, is highly improbable, it might make sense to prepare for such an unlikely scenario, if only as a form of insurance. As part of that effort, the United States should guard against China or Russia developing asymmetrical capabilities, ranging from hypersonics to artificial intelligence, that might threaten the survivability of the United States’ own strategic forces. This mission is far easier and less expensive than Cold War–inspired efforts to seek an elusive strategic nuclear advantage.

Over time, the costs of conquest have risen dramatically, and the benefits have fallen.

In the years ahead, the United States will face at least three crucial questions regarding nuclear weapons. What role, if any, will nuclear weapons play against smaller, hostile nuclear states, such as North Korea and possibly Iran? How should Washington respond if a great power uses nuclear weapons at a substrategic or tactical level—for example, if Russia detonates a nuclear device for battlefield or demonstration purposes? Finally, what will become of extended nuclear deterrence in a world in which the United States acknowledges the futility of a strategic nuclear advantage?

Cold War postures or strategic forces would be of little use in any of these scenarios. If the United States sought to disable a rogue regime’s nuclear capability, deter or respond to the tactical use of nuclear weapons by a great power, or strengthen Washington’s commitment to defend an ally, it would be better to build and deploy powerful weapons whose use would be more credible and compelling. The demonstrated ability to repel a Chinese amphibious assault on Taiwan, for example, or a clear superiority in cyber-operations, artificial intelligence, and space capabilities would be more likely to reassure concerned allies and deter foes than improved nuclear counterforce systems.

Critics will respond that this stance could weaken extended deterrence. Neither the United States nor its allies are eager to concede the obvious—that Washington is unlikely to use nuclear weapons first or even at all, save as a response to an attack on the American homeland. Proclaiming doctrines that are clearly untrue, however, while investing in expensive strategic nuclear counterforce capabilities whose use is unimaginable can have a corrosive effect and both invite complacency and tempt adversaries. Over time, adversaries are more likely to be deterred and allies are more likely to be reassured by tools that Washington might actually use.

The United States could also reconsider its policies on allies acquiring nuclear weapons. Washington retains its desire to limit the spread of nuclear weapons and should work hard to prevent proliferation. Almost 80 years after World War II, however, nuclear acquisition by democratic allies such as Germany or Japan would be far less threatening than during the Cold War, when it could have torn apart the Western alliance or provoked a Soviet attack. A future world with, for example, a nuclear Australia, South Korea, Sweden, Turkey, or Vietnam would hardly be ideal for the United States. It would, however, be far worse for China and Russia.

The most important change Washington must make, however, is to its mindset. Cold War thinking about nuclear strategy has long outlasted the conflict itself. More than three decades into the post–Cold War era, policymakers have still not managed to fully update their view of the nuclear threats the United States faces and the proper way to deal with them. For the sake of U.S. national security and for the stability of the world, they need to pick up the pace.

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  • FRANCIS J. GAVIN is Giovanni Agnelli Distinguished Professor and Director of the Henry A. Kissinger Center for Global Affairs at Johns Hopkins University’s School of Advanced International Studies.
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