Withdrawing Credibility

The recent US decisions to withdraw 5,000 troops from Germany, not to deploy a long-range fire unit, and cancel the deployment of 4,000 rotational troops to Poland have serious military implications for NATO’s deterrence posture. But focusing on counting troops and missiles risks not seeing the forest through the trees. The decisions’ adverse impact on the credibility of the American security commitment to Europe is far more consequential. 

The announcements from Washington should not have surprised Europeans. Even if Germany and Poland were supposedly “model allies”, the Trump administration has long signaled that it intends to reduce its military footprint in Europe. At his first visit to NATO headquarters in February 2025, Secretary of Defense Pete Hegseth urged Europeans to assume “primary responsibility” for Europe’s conventional defense. The National Defense Strategy also asserted that the United States would provide only “critical but more limited” support for Europe’s defense. During his first term, President Donald Trump planned to withdraw 12,000 US troops from Europe, but the Biden administration scrapped the idea. 

Many analysts therefore expected changes to US force posture to come earlier in Trump’s second term. Perhaps the best explanation for the delay is a combination of reasons: logistical challenges to relocating thousands of troops, a belated appreciation of the importance of US bases in Europe for power projection in the Middle East, opposition in Congress (which led the legislature to include passages in the 2026 National Defense Authorization Act that constrain the administration’s ability to significantly reduce US forces in Europe), and a White House preoccupied with other crises and regions. 

What has changed now is the focus of the president’s attention. The timing of the decision—at least regarding the changes to the US posture in Germany—was probably prompted by wider frustration about European reluctance to join the US war effort against Iran and comments from German Chancellor Friedrich Merz. During a visit to a high school in late April, he, seemingly offhand, told students that the United States “had no strategy” and was being “humiliated” by Iran. This drew Trump’s ire. He lashed out against the chancellor on social media, threatened to withdraw US troops, and followed through on that shortly thereafter. The enormous depletion of scarce munition inventories due to the Iran war may have contributed to the decision not to deploy the army’s long-range fire battalion, the 2nd Multi-Domain Task Force. 

European Deep Deterrence Gaps 

For now, the withdrawals are modest. But details remain scarce. According to recent press reports, the 2nd Cavalry Regiment is tapped to be withdrawn from Germany. Although the tank brigade is based there, it operates across Central and Eastern Europe and would likely have an operational role on NATO’s eastern flank. It remains unclear where the regiment will go. If it were to be stationed in Poland or the Baltic states, the move will not weaken NATO’s deterrence posture. (For details on the cancellation of the troop deployment to Poland, refer to this text by Philip Bednarczyk). Either way, Europeans should be able to replace the tank brigade. 

The decision not to deploy the lang-range fires battalion is more serious because Europe suffers from a real deterrence gap. Deep precision strikes (DPS) have long played an important role in US and NATO military planning to counter initially Soviet and then Russian military challenges. Two recent developments have underlined the continued importance of DPS: the collapse of the Intermediate-Range Nuclear Forces Treaty in 2019 after systemic violations by Russia in its pursuit of multiple long-range dual-capable weapons, and the crucial role of DPS in the Russian war against Ukraine. 

Russia now stations long-range cruise and ballistic missiles in its Kaliningrad enclave, which puts European capitals in their range. The lack of reciprocal capability complicates defense planning and undermines Europe’s ability to deter Russia. In 2024, the Biden administration and the German government under Olaf Scholz consequently agreed to temporarily station the 2nd Multi-Domain Task Force equipped with Tomahawk cruise missiles and hypersonic weapons in Germany until a European DPS capability was developed. However, long-range missile projects under the European Elsa program are now not expected to come to fruition before the 2030s. European defense officials are frantically looking for stopgap solutions.

US Credibility Crisis

As serious as the deterrence gap in DPS strike capabilities are, the bigger issue is the decision’s impact on the credibility of the US commitment to Europe. Deterrence is the sum of that credibility and military capabilities. For deterrence in Europe to work, Russia needs to believe that the Trump administration would use all remaining US troops and capabilities in a NATO Article 5 scenario. 

Scholarly literature on deterrence identifies several ways to demonstrate resolve to increase credibility. These include deploying trip-wire forces that signal the near-inevitability of participation in any conflict, making public commitments to increase the reputation costs of reneging on those commitments, holding to formal alliance obligations, and communicating that core interests are involved. 

The Trump administration has undermined every one of these. The announced changes to the US force posture appear haphazard and punitive rather than following a coordinated, transatlantic burden-shifting road map (or any strategic rationale) that would be designed to minimize deterrence gaps in Europe. Moreover, the administration’s declared policy to shift the responsibility for conventional defense to Europeans would mean the end of trip-wire forces, thereby undermining the credibility of the US nuclear umbrella. 

Since initially coming into office in 2017, Trump has habitually questioned NATO’s value. In the wake of the Iran war, for example, he called the alliance a “paper tiger” that “[Russian President Vladimir] Putin is not afraid of”. He added that the United States was “strongly considering” withdrawing from NATO. Secretary of State Marco Rubio echoed the sentiment by saying that the administration would “re-examine whether or not this alliance … is still serving” the United States. Such rhetoric is the opposite of sending signals of resolve. And past White House threats to annex Greenland reduce the collective defense commitment to absurdity.

The current administration speaks and behaves as though it no longer perceives European security as a key US national interest. From dramatically reducing its support to Ukraine, via seeking a normalization of relations with Russia, through to prioritizing the Western hemisphere, the Indo-Pacific, and the Middle East, the United States and Europe are diverging in their perceived core interests.

None of this goes unnoticed in Moscow. Since deterrence credibility is subjective and lies in the eyes of the adversary, it is now likely that Putin increasingly questions the US commitment to Europe, raising the risk that Russia will test NATO in the next few years. In response, Europeans should fast-track programs to close the DPS capability gap. They should make contingency plans for defending the continent without American support. They also need to start the process of Europeanizing NATO. Doing that requires sustainably higher defense spending, assuming greater responsibility for command positions in the alliance, and rethinking nuclear alternatives. In other words, they need to forge a European way of war. Europeans also need to stop worrying that rearming creates a self-fulfilling prophecy of hastening an American withdrawal. The US shift is structural, and signs of weakness will not sway Washington.

Any residual credibility of the US deterrent remains better than none. But the American security commitment to Europe is perhaps less credible than it has ever been. Europeans would be wise to prepare for a world in which the United States does not come to their rescue.

The views expressed herein are those solely of the author(s). GMF as an institution does not take positions.