There are good reasons to anticipate evolutionary, rather than revolutionary, change to NATO and European defense.
The Trump administration’s decision to press for improved relations with Russia, along with the president’s insistence upon an urgent peace deal between Ukraine and Russia, has led to serious concern within the European community. In reaction to the dramatic shift in U.S. policy and its implications for European security, political leaders within the European Union (EU) have become more outspoken about the need to improve their own defense and deterrence capabilities.
In a meeting in Brussels on March 6, 2025, these leaders continued their ongoing discussions about how to finance significant increases in European defense spending, including loans to support transnational investments in missile defenses, anti-drone systems, and other defense technologies. Both France and the United Kingdom have suggested they might even be willing to deploy peacekeeping troops to Ukraine to ensure a postwar peace settlement. In addition, French president Emmanuel Macron said he planned to discuss with European allies the possibility of using France’s nuclear deterrent to protect its European allies.
As one example of European leaders’ sense of urgency, the Danish prime minister Mette Frederiksen noted that “the most important thing now is, to be very frank, to rearm Europe, and I don’t think we have a lot of time.” She added that the European Community should “spend, spend, spend on defense and deterrence.”
Similarly, Ursula von der Leyen, President of the European Commission, said that “Europe faces a clear and present danger” as leaders met with Ukrainian president Volodymyr Zelensky to discuss the possible outlines of a viable peace plan for ending the war in Ukraine.
The challenge for EU and other European policymakers lies beyond the perceived need to support Ukrainian independence and sovereignty against Russian aggression. The other part of Europe’s challenge is to redefine its relationship with its American partner. The details of any peace agreement between Ukraine and Russia lie further ahead, in the diplomatic mélange of Russian, Ukrainian, U.S. and European interests and priorities.
The elephant in the room is whether the Trump administration’s push for normalization of relations with Russia would repolarize the international system and leave the defense of Europe to the latter alone. If so, it follows that the status of NATO would require redefinition of responsibilities and restructuring of shared commitments. Under this assumption, changes in policy and military strategy for the United States and Europe would be almost certain to follow.
On the other hand, it is premature to draw the most pessimistic conclusions about future U.S., NATO or European policies with respect to ending the war in Ukraine and supporting a viable post-war security. There are reasons to anticipate evolutionary, rather than revolutionary, change to NATO and European defense, including military and security commitments.
The United States and Europe must establish clear markers for what is acceptable and unacceptable in any peace agreement between Ukraine and Russia. If the United States, NATO, and the EU are not in sync in this respect, protracted and frustrating negotiations are likely to follow. Therefore, a distinction must be made between what is diplomatically viable and militarily attainable, and what is not. Professional diplomats will eventually get down to the dirty details, based on at least three assumptions made by their respective political leaderships. These assumptions will be the foundations for the development of any political and military agreements to follow.
First, and foremost, among these assumptions is that security and stability in Europe requires a strong American partner and leader. NATO is the military face of an American security guarantee for a free Europe. It is also the organizational template for coordinating military planning for European deterrence and defense. This coordination includes investments in force structure, modernization, readiness, and sustainability, which are updated regularly and embedded into exercises and training for modern combined arms warfare. Included in this menu are the reliability and survivability of the nuclear forces available to NATO and under the national control of the United States, UK, and France. No foreseeable evolution of the EU or other European-based political and military structures could provide the deterrent value that NATO offers against the potential threat of conventional warfare or nuclear coercion.
Second, the United States and Europe must aim for complete coordination when speaking with Russia. Even in the aftermath of a successful peace settlement, the United States and its allies cannot rule out Russian revanchism. Russia may decide to ride out the second Trump administration and await his successor before taking another shot at destabilizing or overrunning Ukraine. Once it subverts and overthrows the regime in Kiev and replaces it with a Russian puppet, Russia’s appetite may grow. So long as Putin retains absolute power in Russia, his nostalgic determination to rebuild the Soviet Union, or enlarge Russia’s sphere of interest, must be factored into U.S. and European defense planning.
Third, some assume that rising threats in Asia require enhanced American focus and a lesser commitment to Europe. The proposed “pivot” to Asia recognizes the growing economic competition and military threat from China, and privileges the Indo-Pacific theater of operations in military planning. The Asian pivot did not originate with Trump. The Obama administration began this shift in emphasis and it continued through the first Trump and Biden presidencies.
However, it would be wrong to assume that a defensive posture in Europe would free up resources and attention for American deterrence and defense in the Indo-Pacific. The two theaters of military operations present different deterrence and defense challenges. In addition, perceived weakness in U.S. and allied deterrence and defense in Europe could embolden China to test American resolve in Asia, including with respect to a possible attack on Taiwan. Credibility crosses the lines of geography.
Related to this is the military alliance between China and Russia and the coordination of their military training and planning for future wars. Some have reacted to this challenge by insisting that the United States cozy up to Russia in order to play the Kremlin off against the Politburo, a reversal of former President Richard Nixon’s Cold War maneuver of playing China against Russia. Under present conditions in world politics, however, it is doubtful that such a ploy would alter either Russia’s or China’s military-strategic priorities or threat perceptions.
If the preceding arguments are correct, then incremental adjustments in U.S. and allied NATO defense preparedness, with or without EU assistance, should provide the necessary deterrent and defense recipes for Europe. It is also true that military preparedness alone cannot win the day. It must be supplemented by a strategic, diplomatic, informational, and economic program that will maintain the commitment of domestic publics in NATO and the European community to shared sacrifice and preparedness even in peacetime.
Stephen Cimbala is a Distinguished Professor of Political Science at Penn State Brandywine and the author of numerous books and articles on international security issues.
Lawrence Korb, a retired Navy captain, has held national security positions at several think tanks and served in the Pentagon in the Reagan administration.
Image: Frederic Legrand / Shutterstock.com.