为什么特朗普要求从德国撤回5000名美军会损害美国利益

President Donald Trump announced on May 1, 2026, that the United States will withdraw 5,000 U.S. troops from Germany – personnel who had been deployed there as a response to Russia’s invasion of Ukraine.

Germany-U.S. tensions started after the U.S. invasion of Iran. German Chancellor Friedrich Merz refused to support Trump’s war and stated that Iran had humiliated Washington’s leadership by closing the Strait of Hormuz. Trump followed the initial U.S. troop withdrawal announcement with threats to pull more armed forces.

U.S. troops will depart Germany over the next six to 12 months, leaving about 31,000 troops in the country.

The Trump administration’s decision to withdraw personnel comes after weeks of mounting tensions between the U.S. and NATO members. The United Kingdom and Portugal have restricted Washington’s ability to use its bases in those countries for certain activities related to the Iran war.

Trump also threatened to withdraw U.S. troops from Spain and Italy over their opposition to the war and refusal to help the U.S.

“Why shouldn’t I?” Trump said on April 30, 2026, referring to possible U.S. troop withdrawal from the two European countries. “Italy has not been of any help. Spain has been horrible. Absolutely.”

These remarks suggest the Trump administration views U.S. troop withdrawal as punishment for noncompliant European allies. But the reality is more complicated. Although this proposed 5,000-troop reduction is less than 15% of current U.S. forces in Germany, its logic and consequences speak to broader issues of power projection.

As experts in international relations, foreign policy and security cooperation, we have studied the relationship between U.S. military deployments and their host countries for years. While U.S. deployments contribute to the security of the host state, having troops based in Europe and other countries provides the U.S. with significant flexibility for pursuing its own foreign policy goals.

US deployment levels

Europe has historically been one of the regions with the highest concentrations of U.S. military personnel deployed overseas.

Since the end of the Cold War, for example, Italy has hosted between 20,000 and 40,000 personnel, and Spain between 2,000 and 7,000 personnel. Germany has regularly hosted the largest deployments. At the end of the Cold War, the U.S. maintained approximately 227,000 military personnel in Germany. Though Europe remains a significant location for basing U.S. troops, this number fell dramatically in the 1990s, hovering between 50,000 and 75,000 for most years since then.

US power projection

Historians and policymakers often explained U.S. deployments to Europe as a means of deterring the Soviet Union during the Cold War.

Nobel laureate Thomas Schelling described the logic in 1966: Even a small deployment in West Berlin served as a trip wire, ensuring that Soviet incursions would trigger a much larger military response from the U.S. and its European allies.

But a closer look at U.S. foreign policy challenges this view. While U.S. troops stationed in Europe were meant to defend Europe, their utility has extended far beyond that.

U.S. military bases and deployments provide the U.S. with greater flexibility and opportunities to pursue its foreign policy goals. By forward positioning military personnel and assets, the U.S. can reduce response times during crises, as well as the costs of moving its military resources into strategic positions.

Foreign deployments can convince countries not to attack countries that host them. During the Cold War, for example, the U.S. deployed nuclear weapons to Incirlik Air Base in Turkey, a NATO ally. Turkey’s close proximity to the Soviet Union increased the U.S.’s ability to challenge its superpower rival with these weapons.

These missiles were famously later withdrawn during the Cuban missile crisis in 1962, giving the U.S. something to bargain with in persuading the Soviets to remove their missiles from Cuba.

Larger military engagements, such as the Vietnam War or the wars in Iraq and Afghanistan, have typically relied on U.S. military facilities in allied states that are closer to the conflict. During the Vietnam War, U.S. bases in Germany, Japan and the Philippines were used as staging areas through which U.S. personnel and equipment moved on their way in or out of Southeast Asia.

U.S. facilities in Germany, such as Ramstein Air Base and Landstuhl Regional Medical Center, have been integral to combat operations, satellite control of drones and treating U.S. personnel wounded in combat. Landstuhl has admitted over 97,000 wounded soldiers since its founding in 1953 and has already treated service members injured during the ongoing Iran war.

Further, military equipment such as radar and interceptor missiles often have limited ranges. Deploying this equipment closer to rival countries can increase the chance of successfully intercepting and destroying incoming missiles.

Humanitarian benefits

Beyond warfare, U.S. humanitarian relief and disaster response operations often benefit from U.S. bases.

For instance, after a large earthquake struck Japan in 2011, U.S. personnel and facilities located in and around Japan enabled the rapid mobilization of relief operations.

In 2004, a powerful earthquake in the Indian Ocean triggered large tsunamis, affecting millions of people in nearby countries. U.S. personnel stationed at Yokota Air Base near Tokyo provided relief and supplies to people throughout Southeast Asia and as far as eastern Africa.

Similarly, after an earthquake in Turkey in 2023, U.S. medical personnel relocated from Germany to Incirlik Air Base to help provide relief.

Beyond their humanitarian benefits, these missions can increase favorable views of the U.S. More positive public views of America may also make foreign governments more likely to support U.S. foreign policy goals.

Lower costs for the US

Host states often make direct and indirect contributions to the costs of hosting and sustaining U.S. personnel. These can range from direct financial transfers to construction, tax reductions and subsidies. Japan and South Korea increased the amount they pay to host U.S. troops after Trump demanded they do so in 2019.

U.S. equipment – from tanks and trucks to planes and ships – also often relies on a host country’s infrastructure to operate and move within the host country. Germany, for example, paid over US$1 billion for construction costs and the stationing of U.S. troops in Germany during the 2010s.

Not all countries that host U.S. troops invest as much in their infrastructure as Germany does, and having those troops elsewhere could prove far more costly than having them in Germany.

Michael A. Allen received grant research funding from the Department of Defense’s Minerva Initiative, the US Army Research Laboratory, and the US Army Research Office from 2017 to 2021.

Carla Martinez Machain has received funding from the Department of Defense’s Minerva Initiative, the US Army Research Laboratory, and the US Army Research Office.

Michael E. Flynn has received funding from the Department of Defense’s Minerva Initiative, the US Army Research Laboratory, and the US Army Research Office.