The first year of Joe Biden’s presidency ended as it began, with the United States facing crises on multiple fronts. In the spring of 2021, there were simultaneous war scares in eastern Europe and the western Pacific, thanks to a Chinese intimidation campaign against Taiwan and a Russian military buildup on the Ukrainian border. At the start of 2022, the world was no calmer. China’s menacing maneuvers near Taiwan continued. Russian President Vladimir Putin, having mobilized an even bigger force near Ukraine, was threatening to start Europe’s largest war in decades. Meanwhile, Tehran and Washington looked to be headed for a renewed crisis over Iran’s nuclear program and its drive for regional primacy. Being a global superpower means never having the luxury of concentrating on just one thing. 

That is a rude lesson for Biden, who took office hoping to reduce tensions in areas of secondary importance so that the United States could focus squarely on the problem that matters most: China. It also indicates a larger weakness in Washington’s global posture, one that Biden now owns but did not create.

The United States is an overstretched hegemon, with a defense strategy that has come out of balance with the foreign policy it supports. Biden’s first year has already shown how hard it is to manage an unruly world when Washington has more responsibilities—and more enemies—than it has coercive means. Over the longer term, a superpower that fails to keep its commitments in line with its capabilities may pay an even heavier price.

ASIA FIRST

Biden’s initial theory of foreign policy was straightforward: don’t let smaller challenges distract from the big one. Of all the threats Washington faces, Biden’s interim national security strategy argued, China “is the only competitor” able to “mount a sustained challenge to a stable and open international system.” That challenge has become greater as China has accelerated its efforts to overturn the balance of power in Asia. When Biden took office, U.S. military leaders publicly warned that Beijing could invade Taiwan by 2027. Biden was not naive enough to think that other problems would simply vanish. With trouble brewing on this central front, however, he did seek a measure of calm on others.

Biden avoided another doomed “reset” with Russia, but held an early summit with Putin in a bid to establish a “stable and predictable” relationship. He also sought to find a path back to the 2015 nuclear deal with Iran, thereby reducing the growing risk of confrontation in the Middle East. Finally, Biden ended the U.S. war in Afghanistan, a decision he justified by arguing that it was time to refocus attention and resources on the Indo-Pacific. Relations with U.S. allies followed the same pattern: the administration dropped U.S. opposition to the Nord Stream 2 gas pipeline linking Russia and western Europe, wagering that ending a contentious dispute with Germany would make it easier to win Berlin’s cooperation vis-à-vis Beijing.

Biden’s emerging defense strategy has a similar thrust. The Trump administration made a major shift in U.S. defense planning, arguing that the Pentagon must relentlessly prepare for a conflict against a great-power challenge—particularly from China—even though that meant accepting greater risk in other regions. Biden’s Pentagon likewise spent 2021 focusing on how to deter or defeat Chinese aggression, withdrawing scarce assets such as missile defense batteries from the Middle East, and making longer-term budgetary investments meant to “prioritize China and its military modernization as our pacing challenge.”

TROUBLE EVERYWHERE

Biden is undoubtedly right that the Chinese challenge overshadows all others, despite unresolved debates in Washington over exactly when that challenge will become most severe. His administration has made major moves in the Sino-American competition during its first year—expanding multilateral military planning and exercises in the western Pacific, focusing bodies such as NATO and the G-7 on Beijing’s belligerence, and launching the AUKUS partnership with Australia and the United Kingdom. Yet Biden hasn’t enjoyed anything resembling a respite on other fronts.

The U.S. withdrawal from Afghanistan precipitated the collapse of the government there, generating a near-term crisis that consumed Washington’s attention and leaving longer-term legacies—strategic and humanitarian—that are likely to do the same. Meanwhile, a brutal internal conflict in Ethiopia destabilized one of Africa’s most important countries. Most problematic of all, U.S. relations with Iran and Russia became worse, not better.

The United States is an overstretched hegemon, with a defense strategy out of balance with the foreign policy it supports.

Iran has taken a hard-line stance in negotiations on a revived nuclear deal while steadily decreasing the amount of time it would need to produce a potential weapon. Tehran’s proxies have also conducted periodic attacks against U.S. personnel and partners in the Middle East as part of an ongoing effort to force an American withdrawal from the region.

Putin, for his part, has authorized or at least permitted significant cyberattacks against critical infrastructure in the United States. He threatened war against Ukraine in the spring and has now mobilized forces for what U.S. officials fear could be a major invasion and prolonged occupation of that country. To preserve the peace, Moscow has demanded an acknowledged Russian sphere of influence and the rollback of NATO’s military presence in eastern Europe. What exactly Putin has in mind for Ukraine is uncertain, but “stable and predictable” is clearly not how he envisions his relationship with the United States.

These are ominous signs for 2022. The United States could find itself facing grave security crises in Europe and the Middle East in addition to persistent and elevated tensions in the Pacific. And these possibilities hint at a deeper problem in U.S. statecraft, one that has been accumulating for years: strategic overstretch.

MORE WITH LESS

Facing trouble on many fronts is business as usual for a global power. U.S. foreign policy—and the defense strategy that buttresses it—has long been designed with that problem in mind. After the Cold War, the United States adopted a “two major regional contingencies” approach to defense planning. In essence, it committed to maintaining a military large and capable enough to fight two serious wars in separate regions at roughly the same time. U.S. planners were under no illusion that Washington could fully indemnify itself against all the threats it faced if they happened to manifest simultaneously. Their aim was to limit the risk inherent in a global foreign policy by ensuring that an enemy in one theater could not wage a successful war of aggression while the Pentagon was busy with a crisis in another. Just as the United Kingdom, the superpower of its day, had a two-power naval standard in the nineteenth century, a unipolar United States had a two-war standard for a generation after 1991.

Over time, however, the two-war standard became impossible to sustain. The defense spending cuts associated with the Budget Control Act of 2011 (later compounded by the sequestration cuts of 2013) forced the Pentagon to adopt a somewhat stingier “one-plus” war standard aimed at defeating one capable aggressor and stalemating or “imposing unacceptable costs” on another. Meanwhile, the number of threats was increasing. During the post-Cold War era, the Pentagon worried mostly about potential conflicts in the Persian Gulf and the Korean Peninsula. But the events of 2014 and 2015—the Islamic State’s rampage through Iraq and Syria, Russian aggression in Ukraine, and China’s drive for dominance in the South China Sea, along with ongoing operations in Afghanistan—showed that U.S. allies and interests were now imperiled in several regions at once.

Leaders in Moscow and Tehran see that the United States is stretched thin and eager to pay more attention to China.

Washington’s enemies were also growing more formidable. The two-war standard was primarily focused on rogue states with second-class militaries. Now, the United States had to contend with two near-peer competitors, China and Russia, that boasted world-class conventional capabilities alongside the advantages that would come from fighting on their own geopolitical doorsteps. By the end of Barack Obama’s presidency, it was an open question whether the United States could defeat China if Beijing assaulted Taiwan, or Russia if Moscow invaded the Baltic region. What was clear was that any such war would require the overwhelming majority of the Pentagon’s combat power, along with virtually all of its airlift and sealift capabilities.

This realization prompted a major change in U.S. defense planning. The Trump administration’s defense strategy declared that the two-war standard was history. The U.S. military would henceforth be sized and shaped to win one major war against a great-power competitor. The United States would still be capable of “deterring” aggression in other theaters, but, as a bipartisan commission that included several current Biden administration officials pointed out, how exactly the Pentagon would do so without the capability to defeat such aggression remained ambiguous.

Shifting to a one-war standard was a sensible way to motivate the lethargic Pentagon bureaucracy to find creative solutions to the urgent, daunting challenge of war with a near-peer rival. It involved a sober recognition that losing a great-power war could inflict a death blow on the U.S.-led international order. Yet the 2018 defense strategy was also an acknowledgment of overstretch: the United States could focus on its primary challenge only by reducing its ability to focus on others. This limitation is the root of the problem Biden has inherited, and it has some dangerous implications.

THE CREDIBILITY GAP

The most glaring danger, highlighted by the concurrent crises in eastern Europe and East Asia, is that the United States could have to fight wars against China and Russia simultaneously. This would indeed be a nightmare scenario for a one-war military. But it wouldn’t take a global security meltdown to reveal the problems caused by Washington’s predicament. 

First, overstretch limits U.S. options in a crisis. Where the United States should draw the line against Russian aggression in eastern Europe, how hard it should push back against Tehran’s provocations in the Middle East, and whether it should use force to prevent Iran from becoming a nuclear threshold state are matters that reasonable people can debate. But the fact that the United States increasingly has a China centric defense strategy has a constraining effect in other theaters. If a U.S. president knows that the Pentagon will need everything it has for an all-too-plausible war with China, he or she will be less inclined to use force against Iran or Russia, lest Washington be caught short if violence erupts in the Pacific.

This issue leads to a second problem: the loss of diplomatic influence in situations short of war. Since the Taiwan and Ukraine crises of early 2021, some observers have speculated that Putin and Chinese President Xi Jinping are coordinating their coercion as a way of threatening Washington with a two-front war. The reality is that explicit coordination is hardly necessary to profit from U.S. overextension.

Historically, overstretched superpowers have eventually faced hard choices.

Leaders in Moscow and Tehran can see that the United States is stretched thin militarily and eager to pay more attention to China. This gives them an incentive to push Washington harder in hopes of achieving gains at the expense of a distracted superpower. As the Russia expert Michael Kofman has written, Putin’s strategy of using military coercion to revise the post-Cold War order in Europe is premised on his belief that the “greater threat from China” will eventually “force Washington to compromise and renegotiate.” The more intense its focus on China, the higher the price the United States may be willing to pay for restraint in other places.

The perils of overstretch, however, are not confined to secondary theaters. Weakness at the periphery can ultimately cause weakness at the center. A decade ago, the United States withdrew its forces from Iraq to economize in the Middle East and pivot toward the Pacific. Iraq’s subsequent collapse forced Washington to reengage there, fighting a multi-year conflict that devoured resources and attention.

Similarly, if the United States finds itself in a showdown with Iran or if Russia attempts to revise the status quo in eastern Europe, Washington may once again find itself pivoting away from the Pacific to reinforce under-resourced regions that still matter to U.S. security. America’s defense strategy is increasingly focused on the Indo-Pacific, but its foreign policy remains stubbornly global. That’s a recipe for trouble all around.

TOUGH CHOICES

To be clear, military power is hardly the only thing that matters in global affairs. But it is a necessary component of an effective foreign policy, if only because force remains the ultimate arbiter of international disputes. Xi, Putin, and other U.S. adversaries are unlikely to be swayed by Biden’s “relentless diplomacy” unless they are also awed by the military power that backs it up.

Historically, overstretched superpowers have eventually faced hard choices about how to address mismatches between commitments and capabilities. When the United Kingdom found itself with more rivals than it could handle in the late nineteenth and early twentieth centuries, it began appeasing those that were less dangerous and proximate—including the United States—to concentrate on containing Germany. When the Korean War revealed that Washington’s containment policy outstripped its military resources, the United States was forced to undertake a significant defense buildup to close the gap.

The Biden administration may try to skirt this dilemma by managing tensions with Iran, Russia, and other challengers while encouraging allies in Europe and partners in the Middle East to take greater responsibility for their own defense. That’s an understandable instinct. In the near term, both the geopolitical costs of true retrenchment and the financial costs of rearmament may seem to exceed the difficulties of muddling along. Yet Biden’s first year has already shown that overstretch inflicts damage on the installment plan. Eventually, the world will punish a superpower that allows its strategic deficit to grow too big for too long.

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