Rachel Tausendfreund: Europe in a US grand strategy of restraint

Restraint is not a word that seems to obviously apply to Donald Trump and his second administration. In terms of challenging and calling out allies and partners, and some adversaries there has been quite the opposite of restraint. Also the operation to capture President Nicolás Maduro in Venezuela in January 2026 or the current war against Iran have not been consistent with a more reserved foreign policy. And yet, there are consistent elements of a strategy of restraint evident in the second Trump administrations policy toward Europe. This can be seen in its positioning toward Ukraine as well as the restructuring and rebalancing in NATO. It is important for Europe to focus in on these aspects of current US policy if it wants to understand how a US grand strategy of restraint will affect Europe.

First of all, it is important to explain and define restraint in the foreign policy context. A foreign policy of restraint rejects the role of global policeman for the United States and holds that the United States should ease tensions with adversaries, shrink its overseas footprint and alliance commitments, and set a much higher bar for the use of force. It emerged as a dissenting school in the early 1990s, when the Soviet collapse removed NATO’s formal justification and figures like Christopher Layne, Eugene Gholz, Daryl Press and Harvey Sapolsky (“Come Home, America,” 1997) argued that “deep engagement” or primacy had outlived its rationale. Barry Posen’s Restraint (2015) is also a seminal work in the school, from which also the term restraint/restrainer is taken.

Theoretically it sits in structural realism, but in its defensive variant: the core American interest is counterhegemonic, preventing any single state from consolidating a region with the latent economic and demographic weight to rival the United States, which narrows the list of places that matter to Europe and the Indo-Pacific, and the recommended instrument there is offshore balancing — let local states do the balancing first and intervene only if they fail. Two further theoretical moves distinguish it from ordinary burden-sharing complaints. The first is Mancur Olson and Richard Zeckhauser’s 1966 collective-action logic, which predicts that in an alliance of very unequal members the largest will systematically overpay and the smaller will free-ride, making decades of American pleading structurally futile and making withdrawal of the subsidy, not persuasion, the only effective lever. The second is a security-dilemma argument turned inward: forward deployments and expansive commitments do not merely cost money but generate entanglement, moral hazard among dependents, and wars that would otherwise not be fought — which is why restrainers count the loss of European staging bases for Middle East operations as a benefit rather than a cost (as Jennifer Kavanaugh and Justin Logan recently argued in Foreign Affairs). Restraint is thus distinct from isolationism, which rejects engagement as such; it accepts trade, diplomacy and offshore naval power while rejecting permanent garrisons and open-ended guarantees.

While restraint shares much DNA with the realist school of international relations, there are also progressive arguments pushing toward more restraint. Though it is nascent, there are indications that a more restraintist bipartisan consensus could emerge. The strength of the restraintist trend has to do with the long, expensive, and unsuccessful wars in Afghanistan and Iraq and American war fatique. Additionally, there are two material pressures often cited — American fiscal deterioration and the fact that China, unlike the Soviet Union, is a genuine economic peer — which is why even analysts who reject restraint on the merits increasingly concede that some version of it is arriving regardless.

NATO 3.0: The implications for Europe

In the context of European security, Elbridge Colby, the undersecretary of war for policy, coined the term NATO 3.0 to indicate what a US strategy of restraint (or at least more restraint) means for European security. In his own formulation at the Atlantic Council in late August: NATO 3.0 will be an alliance grounded in “flexible realism,” focused on warfighting readiness, able to deter and defend in the North Atlantic area “even under conditions of simultaneity,” with allies taking primary responsibility for Europe’s conventional defense. This last bit is the crucial point. The goal is to shift the burden for conventional defense to European shoulders.

A fully restraintist approach would go further. Restraint proper treats the American presence as the obstacle and prescribes removing it on a schedule to force European adaptation. NATO 3.0 treats the presence as leverage. Colby’s line is “the United States is not leaving Europe,” and he has praised Germany’s military strategy as a credible route to NATO 3.0. It should be viewed as a reallocation of responsibilities rather than a US exit. An open question is how much shifting can really happen if the US retains command-and-control.