Last week, NATO began its annual Steadfast Noon exercise to ensure the alliance’s nuclear readiness, even as the Trump administration pursues a policy that threatens to undermine it.
Launched in February, NATO 3.0 is the brainchild of Elbridge Colby, the undersecretary of defense for policy. At its core is the assumption that the United States can rapidly wind down its conventional commitments to Europe while retaining its leading role in the alliance, so long as Europe continues to rely on the U.S. nuclear guarantee. Colby presents this shift as a rebalancing of the alliance, enticing European states to take responsibility for the continent’s conventional defense as Washington turns its attention to the Indo-Pacific.
The approach is Washington’s attempt to have it both ways—to cut back without sacrificing its influence or affecting extended nuclear deterrence. In reality, however, it would compromise Europe’s defense, diminish Washington’s sway, weaken the U.S. nuclear guarantee, and generate proliferation risks—ultimately undercutting the policy’s objectives and U.S. national interests.
Colby’s vision is already reshaping the U.S. footprint in Europe. In May, the Department of Defense announced plans to withdraw roughly 5,000 troops from Germany and cancel the deployment of a long-range strike battalion there. The U.S. rotational brigade in Romania returned home without replacement last October, and reports suggest another 25,000 to 40,000 troops could leave Europe.
Washington has also proposed cutting its contribution to the NATO Force Model—the pool of forces made available for NATO operations—by one-third to one-half. The United States is reportedly planning to significantly reduce the aircraft and warships available in a crisis, including an aircraft carrier, reconnaissance aircraft, dozens of F-16 and F-15E jets, and potentially half of the current U.S. armed MQ-9 drone supply currently in Europe.
As conventional forces recede, nuclear forces are expected to play a larger role. Colby has pledged Washington “will continue to provide the U.S. extended nuclear deterrent,” and there are reports that the United States is considering expanding the basing of dual-capable aircraft and the deployment of nuclear warheads beyond the alliance’s current six host countries, potentially to Poland and the Baltic states. According to two anonymous sources cited by the Financial Times, the additional nuclear presence is meant to demonstrate the resilience of the U.S. nuclear umbrella despite the conventional drawdown.
Yet convincing an adversary that the U.S. president would risk New York to save Riga has always been a tall order. Historically, Washington has bolstered the credibility of that commitment by ensuring that a conventional attack on NATO territory could trigger unpredictable nuclear escalation. U.S. troops in Europe thus serve as a trip wire: A president might hesitate to order a nuclear strike to defend Germany or Poland but calculate differently if U.S. soldiers were threatened. During the Cold War, stationing U.S. forces on European soil was a deliberate tactic to couple European defense with the protection of Americans.
Colby’s vision, by contrast, treats conventional and nuclear forces as separable domains, assigning responsibility for the former to Europe and the latter to the United States. Such a tidy division may make sense on paper, but it is unrealistic in practice. A hasty U.S. conventional withdrawal would weaken Europe’s ability to defend itself below the nuclear threshold while simultaneously eroding the credibility of the U.S. nuclear guarantee. It is a dangerous, double-edged experiment that undercuts both pillars of deterrence at once.
Partitioning conventional and nuclear responsibilities also creates new challenges for escalation management. For instance, Russian military doctrine reflects concerns about NATO using conventional weapons to conduct counterforce strikes against Russia’s nuclear arsenal—a scenario in which the two domains overlap. Assigning conventional responsibility to Europe and nuclear responsibility to the United States does not produce a clean split. Conventional strikes may hit strategic targets, and Moscow’s threshold for a nuclear response cannot be known in advance. NATO 3.0 would bifurcate the escalation ladder, fragmenting command, complicating allied operations, and giving Moscow new openings to exploit divisions within the alliance.
This problem is compounded by Europe’s dependence on the United States for conventional long-range strike capabilities. The canceled deployments of Tomahawk and Dark Eagle hypersonic missiles underscore the extent of this gap. European alternatives have encountered setbacks; the Kiel Institute estimates, optimistically, that Europe will need at least three to five years to field such capabilities, assuming the necessary funding materializes. Until then, Europe will not be able to hold its own in a high-end conventional conflict with Russia.
Moreover, the notion that the United States would enter a crisis only at the brink of nuclear escalation defies logic. NATO 3.0 effectively hands the president a ready-made rationale for withholding conventional support (“That’s Europe’s job.”) while requiring an affirmative decision to threaten nuclear escalation. It is inconceivable that Washington would avoid the risk of a conventional war on behalf of Europe but somehow accept the far greater risks of a nuclear war. Without meaningful U.S. forces’ involvement in conventional operations and a central role in managing escalation, credible nuclear signaling from Washington is highly dubious. After nearly two years of intense hostility toward European allies, the clearest signal coming from Washington is that Europe is now on its own.
By insisting that the U.S. nuclear umbrella can continue to protect Europe, NATO 3.0 also attempts to push Europe toward greater burden-sharing while keeping a lid on European nuclear proliferation. In March, Colby said the United States would “strenuously oppose” an independent European nuclear program. But if NATO 3.0 deepens allies’ sense of vulnerability, it could backfire and produce precisely the result Colby hopes to avoid.
NATO’s three nuclear powers—the United States, the United Kingdom, and France—all retain independent control over their arsenals and nuclear decision-making. But while Washington and London coordinate through the NATO nuclear planning structure, Paris does not. NATO has historically viewed these separate centers of decision-making as an asset that complicates Russian calculations. In reality, though, the U.S. arsenal remains the backbone of the alliance’s nuclear deterrent, giving Washington immense influence over NATO strategy, planning, and operations. As the U.K. and France strengthen their cooperation on a more explicitly European approach to extended deterrence, the United States risks losing the influence conferred by its long-standing role as the alliance’s ultimate guarantor.
The prospect of extending U.K. and French nuclear protection to the rest of Europe is already gaining traction as doubts about Washington’s reliability grow. In July 2025, the United Kingdom and France committed to independent but harmonizable nuclear forces and established a joint nuclear steering group. In March, French President Emmanuel Macron announced that France would expand its warhead numbers and adopt a forward deterrence framework to deepen European nuclear security cooperation. France and Germany have also set up their own nuclear steering group, and 10 European states are now holding structured bilateral discussions with Paris on nuclear consultation and potential hosting agreements.
For now, these efforts primarily serve as an insurance policy against the possibility of U.S. abandonment. But there is also a danger, albeit still far off, that other NATO states begin to consider acquiring nuclear weapons of their own. Poland is already debating exactly this question. In an address to parliament in March 2025, Polish Prime Minister Donald Tusk suggested the country “pursue the most advanced capabilities, including nuclear and modern unconventional weapons.” He has also brought Warsaw into France’s forward deterrence initiative. Polish President Karol Nawrocki, self-described as “a great supporter of Poland joining the nuclear project,” has argued that the country’s security strategy should rest on developing its own nuclear potential.
New European nuclear states remain a distant prospect, but if NATO 3.0 is intended to reassure allies while discouraging proliferation, the evidence suggests it is having the opposite effect.
NATO 3.0’s underlying intuition—that the United States should encourage greater European burden-sharing without encouraging nuclear proliferation—is sound. The problem is that these objectives cannot be achieved together in such a short window. There are better ways to balance burden-sharing, European security, and Washington’s position in the alliance, and if the Trump administration presses ahead with NATO 3.0, several steps could mitigate the risks.
First, Washington should adopt a formal no-surprises policy of the kind that Dutch officials have proposed, under which allies would receive advance notice of U.S. redeployments and have a voice on potential troop withdrawals, if not a veto. Washington should then establish a phased, multiyear drawdown schedule in consultation with allies, linking reductions to specific European capability benchmarks and joint assessments of the threat from Russia. Washington should also commit to maintaining its support of capabilities that most deter Moscow—specifically for intelligence, surveillance, and reconnaissance; air defense; long-range precision strike; and logistics—until European forces can provide equivalent capabilities, which may be years away.
Congressional consultation is equally important. Support for NATO remains strong on Capitol Hill, and any new trans-Atlantic security bargain will be more durable if it enjoys bipartisan backing. Further, as the Trump administration’s experience has shown, making unilateral cuts risks congressional blowback: The 2026 National Defense Authorization Act restricts the use of funds to reduce U.S. troop levels in Europe below 76,000 for more than 45 days without NATO consultation. A methodical approach that includes both allies and Congress would also help avoid embarrassing moments of policymaking on the fly, such as when Washington withdrew forces from Poland only for Trump to reverse the decision, all at a cost to the American taxpayer.
To address operational challenges, NATO should establish a standing body within its Nuclear Planning Group dedicated to escalation management and other issues created by the proposed division between conventional and nuclear responsibilities. The Defense Department’s six-month review of U.S. force posture in Europe, which is tasked with ensuring that “Europe [is] taking primary responsibility for its conventional defense,” should explicitly assess the implications for conventional-nuclear coordination and extended deterrence.
Washington should also seek greater nuclear coordination within and beyond NATO. One option would be to establish a mechanism linking the NATO Nuclear Planning Group with the French-led bilateral nuclear steering groups. Despite France’s long-standing neuralgia about participating in NATO’s nuclear structures, it would be prudent for these groups to discuss crisis coordination and establish regular communications channels, lest divergences surface for the first time under conditions of considerable danger.
The Trump administration is right that the traditional division of responsibility for European security was unsustainable. But NATO 3.0 rests on an unworkable and dangerous partition between conventional and nuclear capabilities, one that runs counter to the lessons of history and deterrence theory. A phased, consultative redistribution of responsibilities would better preserve deterrence, shift burdens, and protect U.S. influence. Pull back too quickly, and Washington risks leaving behind a weaker NATO and an emboldened Russia eager to test its seams.