The U.S. troop presence in Europe was never meant to be permanent. Overseeing preparations for an Allied landing on the continent to defeat Adolf Hitler’s Germany, President Franklin D. Roosevelt explained in 1944: “the United States will be only too glad to retire all its military forces from Europe as soon as this is feasible.”
Fast forward 80 years, and things turned out very differently than Roosevelt imagined. Europe still hosts around 100,000 U.S. servicemembers and, according to many observers, this number will only increase over the coming years. While support for a significant retrenchment from Europe had gained some momentum prior to Russia’s 2022 attack on Ukraine, the invasion effectively put an indefinite halt on the idea.
The logic behind the consensus view among Washington’s foreign policy elite today is straightforward: U.S. troop withdrawals from Europe would leave a power vacuum inviting further Russian expansionism. This supposed power vacuum would thus critically benefit one of America’s chief geopolitical rivals and undermine U.S. national security.
These fears, however, are vastly overblown. Great powers can, and in the past frequently have, engaged in troop withdrawals without leaving behind power vacuums that their rivals could exploit. As long as the United States continues to exercise dominant influence through its extraordinarily capable and reliable European allies, no meaningful window of opportunity will open for Moscow after a substantial U.S. military departure. Rather than retaining a vast military contingent in Europe — let alone increasing it — for false fears of letting a power vacuum emerge, leaders in Washington should confidently embrace a much-reduced military presence and instead turn their attention to the threat of a rising China in East Asia.
Concerns About Power Vacuums Have a Long History
Fears of power vacuums and their supposed pernicious consequences have long permeated thinking about great-power politics. Among U.S. foreign policymakers, it has become a truth universally acknowledged that, as President Richard Nixon famously told Mao Zedong, “in international relations there are no good choices,” but “one thing is sure — we can leave no vacuums.” The argument seems straightforward: Whenever a great power withdraws from its commitments abroad, it leaves behind a power vacuum that rivals will swiftly fill.
In principle, these fears are well-founded. History is replete with examples in which one great power’s decline abroad inspired its rivals to intensely compete for control over the spaces it left behind. Think, for instance, of how the end of the British empire in the Middle East inspired both the United States and the Soviet Union to vie for influence over a region both deemed vital to their security.
In Europe, the power vacuum that emerged after Nazi Germany’s collapse in World War II forced U.S. leaders to abandon their initial plan of retrenching from the continent as soon as Hitler was defeated. Fearful of an unhindered influx of Soviet influence into Europe, political and military leaders deemed a substantial troop presence on the continent the only reliable way of preventing Moscow from filling the emerging vacuum.
Against this backdrop, it is understandable that fears of power vacuums are once again on the forefront of decision-makers’ minds. With no end to the Russo-Ukrainian war in sight, and given that President Vladimir Putin’s imperial ambitions might extend well beyond Ukraine, it seems all too obvious that a military withdrawal from Europe would turn out to be a strategic disaster for Washington.
Do Troop Withdrawals Invite Rival Expansion?
While this line of reasoning is appealing at first sight, it rests on a deeply flawed understanding of great-power politics. Troop withdrawals need not — and in the past frequently have not — created power vacuums inviting rival expansion.
This most certainly holds true for partial troop withdrawals. Consider the Nixon administration’s decision to withdraw around 20,000 troops from the Korean peninsula during the 1970s. Hoping to cut the U.S. defense budget, which following the Vietnam War had risen to new heights, Nixon sought to significantly reduce the U.S. military’s footprint. Especially as he combined the announcement of troop reductions with promises of additional aid, Nixon’s efforts to withdraw troops from South Korea did little to undermine U.S. authority over the southern part of the peninsula. Consequently, Soviet leaders essentially considered the troop reductions a non-issue: South Korea continued to fall squarely under the hegemony of the United States and no meaningful opening emerged for Moscow to compete for control over the area.
Precisely because they need not erode a great power’s authority — that is, their ability to exercise imperative control — even full troop withdrawals frequently do not pave the way for rival gains. As a case in point, consider the Soviet Union’s retrenchment from Romania during the 1950s. In moving to withdraw the Soviet troop presence in its entirety, Soviet leader Nikita Khrushchev hoped to reach a more sustainable political arrangement that would allow Moscow to exercise influence over Romania without a continued military presence. His efforts to shift from direct to indirect rule without compromising Soviet influence proved remarkably successful. Officials in Washington quickly concluded that, even though the Soviet Union had engaged in a complete military withdrawal from Romania, political circumstances in Eastern Europe remained effectively unchanged. The Soviet Union continued to exercise dominant influence through the Romanian government, which reliably functioned as its proxy. In consequence, no window of opportunity emerged that would have allowed the West to challenge the Soviet Union’s authority over Romania.
Europe Is Capable
There is good reason to believe that U.S. troop withdrawals from Europe today would be similarly successful. America’s partners in Central and Western Europe are the kind of allies that great powers in the past could only dream of. They are extraordinarily capable and reliable proxy actors through which Washington can continue to exercise dominant influence. Consequently, a military departure will not open the continent’s doors to Russian domination.
As the Russo-Ukrainian war has revealed, U.S. troops are not needed to defend Europe against further Russian aggression. Defying the predictions of most pundits, which near-unanimously foresaw a quick Russian victory after the invasion in early 2022, the Ukrainian military has displayed remarkable resilience in its effort to keep Russian forces at bay. Last month, it even went on the offensive by launching a surprise incursion into Kursk Oblast.
While the continued success of Ukraine’s war effort crucially depends on receiving further military aid from the West, there is evidently no military need for the direct involvement of U.S. troops. Without the support of even European troops on the frontlines, Ukraine has been remarkably successful in thwarting Russian offensives. The fact that other European officials appear little inclined to send their troops to Ukraine reveals a crucial truth: If Ukrainian troops alone are able to put up a more-than-decent performance against Russia, there is little reason to be concerned about the military vulnerability of other European states, which have significantly more power at their disposal.
What presently stands in the way of Europe providing more for its own security is the evident lack of willingness among Washington’s European allies to turn their latent power potential — which vastly exceeds that of Russia — into substantially increased military capacity. As Russia invaded Ukraine, the large majority of NATO members fell short of fulfilling their 2 percent of GDP spending pledge, enacted seven years prior, and although NATO Secretary-General Jens Stoltenberg presents himself hopeful that a majority of members will meet this target in 2024, opposition to increased defense spending across the alliance remains strong.
In Germany, the governing coalition has been unable to agree on a marked increase in defense spending, causing significant doubts as to whether the turning point (or Zeitenwende) that Chancellor Olaf Scholz famously announced mere days after the Russian invasion will ever materialize. Similarly, under the leadership of Mark Rutte — the incoming NATO secretary-general — the Netherlands consistently failed to meet the 2 percent target. Notably, Rutte’s resolute opposition to approving more defense spending has left many concerned about how his NATO appointment will affect European security policy going forward.
To some, Europe’s enduring reluctance to spend more on defense underscores the importance of maintaining or even increasing the U.S. military presence. Along these lines, a new report by the U.S. Army War College’s Strategic Studies Institute argues that Europe’s security still critically depends on American military leadership and capabilities.
Yet, this argument overlooks that a marked reduction in U.S. military presence will almost certainly end Europe’s decade-long reluctance to spend more on defense. The key reason is that it is this large American military presence that has enabled European states to largely disregard concerns about their vulnerability in the first place. Being able to rely on the fact that the United States would immediately come to their rescue whenever needed, there was little reason for them to voluntarily share more of the costs of European defense. “Passing the buck” to the United States was the strategically smart thing to do.
Things will fundamentally change once the United States takes steps towards reducing its military presence. A determined withdrawal of U.S. troops will force Washington’s European allies out of their complacency and provide the much-needed impetus to make Scholz’s Zeitenwende a reality. As soon as U.S. allies become convinced that they can no longer trust in U.S. capabilities to defend them when push comes to shove, they will rush to pick up the slack and work towards growing their own capabilities. It is in this sense that — perhaps counterintuitively — a withdrawal of U.S. forces will create an even stronger, not weaker, Europe.
To be sure, U.S. leaders should be prepared for the possibility that Europe’s unwillingness to provide for its own security might persist, at least initially. Changes in both mindset and policy can take some time to take root, and there is no guarantee that the European community — whose individual members more than once have failed to organize a collective response to issues of common concern — will work together to increase European military capabilities following a U.S. withdrawal.
Still, there are good reasons to be optimistic. First, the conventional security threat Russia poses to the continent today will provide a much more effective unifying impetus than the diffuse, non-military threats involved in the 2015 migration crisis or the COVID-19 pandemic. Tellingly, where previous crises failed to forge European unity, Russia’s invasion of Ukraine quickly elicited an effective collective response. Second, by carefully planning for a phased removal of troops, U.S. leaders can increase the likelihood of a successful withdrawal while simultaneously limiting its risks. A gradual retrenchment that is clearly communicated to U.S. allies in advance will give them time to adjust to their new strategic reality without removing the continent’s defenses overnight. Coincidentally, as it leaves much of the U.S. military infrastructure intact for an extended period, implementing a series of phased withdrawals will also ensure that the United States retains the ability to make a military return if Europe were to fail to respond as predicted.
Last but not least, nuclear weapons will offer strong — albeit not perfect — protection against further Russian expansionism after the withdrawal of conventional U.S. capabilities. Irrespective of who they believe will win the White House in November, few experts foresee the end of extended nuclear deterrence. The U.S. nuclear umbrella will continue to deter Moscow from attacking NATO territory, and France and the United Kingdom still retain national arsenals that, in the future, could come to play a central role in supporting a new European security structure.
Europe Is Reliable
U.S. leaders need worry even less about Europe’s continued pro-Western alignment than its ability to defend itself. Historically speaking, states confronting a common threat in their neighborhood almost never align themselves with it but balance against it. Small states that “bandwagon” with a mightier power give up their strategic freedom, accept subordination, and must trust in the strong state’s continued benevolence. Needless to say, states don’t consider this an enticing prospect.
The origins of the European project are a case in point. Fearful of the Soviet Union’s vast military power and seeking to prepare for the contingency of a U.S. departure from the continent, European states joined forces to balance against the Soviet Union. They could have sought to diffuse the Soviet threat by aligning themselves with Moscow, but rightly concluded that this wager would have been unacceptably risky.
Ultimately, the idea that Europe would respond to U.S. troop withdrawals by turning its back on the United States and looking for a closer relationship with another great power — either Russia or China — not only lacks historical precedent but common sense. Both European state leaders as well as the European public have time and time again described their international goals as “keeping America close, Russia down, and China far away.” Decades of close-knit trans-Atlantic cooperation between the United States and Europe have created tight political, economic, and cultural interconnections that neither side will be willing to give up.
It’s Time to Embrace the Benefits of a Reduced Troop Presence
The United States is well-positioned to engage in substantial troop withdrawals from Europe without risking its dominant influence over the continent. Given how capable and reliable America’s regional allies are, it is all but certain that such a move would not pave the way for future Russian gains on the continent.
From a national security perspective, the United States stands to benefit greatly from a reduced troop presence in Europe. Three benefits in particular are worth highlighting.
First and foremost, a reduced presence in Europe will leave the United States better equipped to deal with the threat of a rising China. Unlike Russia — whose military deficiencies have been on display for two years — China has all the markings of a true peer competitor capable of challenging America’s strategic interests in Asia and beyond. Containing Chinese influence in Asia by strengthening U.S. regional allies and deterring Chinese revisionism will place enormous demands on U.S. resources. No matter how powerful the United States still is today, its resource pool is far from bottomless.
Second, there are distinct advantages for legitimacy to wielding influence over others indirectly rather than directly. The permanent deployment of foreign troops within another state’s territory threatens to alienate the local population and thus risks their continued allegiance. While most Europeans remain in favor of close relations with the United States, opposition to the U.S. military presence has been a key talking point of populist parties across the political spectrum. In Germany, both the Sahra Wagenknecht Alliance and the Alternative for Germany have successfully tapped into residual anti-American sentiment among the population.
Last but not least, U.S. leaders will be hard-pressed to argue against a policy that removes U.S. citizens from the threat of physical harm without undermining national security. Although the odds of U.S. servicemembers becoming targets of an attack while stationed in Europe are low, they are not zero. This summer, the U.S. military raised threat levels and security measures across its bases in Europe in response to an ominous “combination of factors,” which many concluded included possible terrorist threats. The episode brought home a point that most had ignored: Any foreign deployment — even in comparatively safe locations such as Western and Central Europe — exposes one’s citizens to serious dangers.
No matter which party wins the presidential elections in November, the odds are that the new administration will be inclined to avoid any major foreign policy changes vis-à-vis Europe. This would be a lost opportunity to challenge the prevailing consensus and embrace a much-reduced troop presence in Europe. Contrary to the conventional wisdom, such retrenchment would not benefit U.S. rivals. It would benefit U.S. national security.
Moritz S. Graefrath is a postdoctoral fellow in security and foreign policy at William & Mary’s Global Research Institute as well as an affiliate scholar with the Nanovic Institute for European Studies at the University of Notre Dame. He earned his Ph.D. in political science from the University of Notre Dame and previously served as a Max Weber fellow at the European University Institute and as a grand strategy, security, and statecraft fellow with a joint appointment at Harvard’s Belfer Center for Science and International Affairs and MIT’s Security Studies Program. (Twitter/X: @moritzgraefrath)
Image: Lance Cpl. Elijah Abernathy
