“Peace through strength,” the phrase often used to define many presidents’ national security vision, is a catchy sound bite. The problem is that no one really seems to know what it means.

The Trump administration’s recent release of its National Security Strategy (NSS) finally provides the phrase some substance. Provoking a litany of fierce hot takes from both critics and supporters, the National Security Strategy reflects only the beginning of a larger sea change. The Trump administration is ushering in a shift away from “neo-Reaganite” primacy, which shackles the U.S. to the interests of the “rules-based international order,” and toward a model grounded in realism, in which America’s actions and policies are aligned in direct service to core national interests. The administration’s forthcoming National Defense Strategy (NDS), a document that translates the pillars of the NSS into concrete defense guidance, is poised to apply this strategic shift to American defense policy.  

Secretary of War Pete Hegseth previewed the change to come at the Reagan National Defense Forum. Traditionally a venue reserved for the Washington national security establishment, rarely has the Reagan National Defense Forum provided a platform for alternative viewpoints. Yet in this year’s keynote address, Secretary Hegseth posited that peace through strength for President Trump means rejecting “utopian idealism” and embracing “hard-nosed realism.”

The secretary aptly harkened back to President Reagan’s Secretary of Defense Casper Weinberger and the principles that guided decisions on the employment of U.S. military power at the time. The Weinberger Doctrine maintained that U.S. military force should be a “last resort,” used strictly in support of “vital national interests” and only employed with “political and military objectives” defined. Reagan’s strategic vision, as the secretary contended, found grounding in realism.  

U.S. defense policy has, post-Reagan and post-Cold War, been unfortunately captivated by the fleeting promises of the “unipolar moment.” Secretary Hegseth unapologetically called out these disastrous distractions — “democracy building, interventionism, undefined wars, regime change” — which have left the United States in a precarious position of underpreparedness to face the increasingly dangerous strategic environment of today. He further challenged the practice often used by opportunistic actors of invoking peace through strength as an umbrella term used to justify everything from endless wars to utilizing the U.S. military as a tool for democracy promotion and “nation building.”

It was a contrarian perspective for the Reagan Forum crowd to hear.

President Trump’s National Security Strategy deserves credit for — echoing the Reagan era  — tightly defining the military’s purpose as “to protect our interests, deter wars, and — if necessary — win them quickly and decisively, with the lowest possible casualties to our forces.” If the National Defense Strategy succeeds in providing more depth to this principle, laying out the limits on the employment of force and the scope of deterrence activities, Trumpian peace through strength gains resilience.

The recent preview of the NDS further suggests that prioritization of America’s core national defense interests — which will force U.S. defense policy back into contact with actual limits — will overarch the document as the main theme.

It’s a much-needed change of course.

As the secretary put it, the “unipolar moment is over, and we have the opportunity to define what comes next.” Peace through strength is not subjective.

It is fair for critics to argue that President Trump is likely to struggle to abide by this ethos, giving in to quick-reaction impulses without concern for consistency. It is also fair to call out his bombing of Iran, watering down a potential peace deal to end the war in Ukraine, and possibly enacting regime change in Venezuela as actions that contradict “America First.”

While the administration has not always lived up to a consistent vision, the forthcoming National Defense Strategy offers hope of recalibration. Secretary Hegseth foreshadowed the policy of prioritization as the way to obtain alignment between America’s core national interests and the allocation of scarce U.S. military personnel, resources, and long-term planning — preserving the “essential connection between ends and means,” as the NSS put it.

The secretary outlined four priority lines of effort: “defending the U.S. homeland,” “deterring China,” “burden-sharing” across U.S. defense alliances and theaters, and revitalizing the U.S. defense industrial base.

Prioritization can correct the decades of post-Cold War misdirection and quagmires that squandered U.S. blood and treasure. But setting priorities must contend with the ever-present bias toward quick action in the current administration, as well as deeply ingrained parochial interests found throughout the Pentagon. Deterring a war with China, the sole military power capable of credibly challenging the United States, is, as the secretary noted, “not a pivot for tomorrow. It is a reality for today.” Taking our eye off the ball in the Pacific by getting bogged down in regime change or extended military campaigns close to home without a focused, achievable objective is a fool’s errand. President Trump and his team should resist such temptations.

Burden-sharing and shifting in non-priority theaters must also remain a condition rather than a suggestion for U.S. allies. The president’s goal for allied countries to devote 5 percent of their GDP to defense spending as the new standard, agnostic of region, is a step in that direction.

Secretary Hegseth took back the high ground on promoting peace through strength. If the forthcoming NDS can hold true to a framework of prioritization — and resist deviation — it will lend greater credibility to President Trump’s vision of a more realistic and restrained defense policy.

It will also provide the best guard against subjectivity, preventing opponents from smuggling in interventionist policies that are no longer popular with the American public. Peace through strength, defined by “hard-nosed realism” over the “utopian idealism” of a bygone era, is poised to yield both a popular and durable American defense policy. Most importantly, however, will be the degree to which the administration remains committed to coherent implementation — peace through strength in practice.

Katherine Thompson is a senior fellow in defense and foreign policy at the Cato Institute. She most recently held senior positions at the Department of War, performing the duties of the Assistant Secretary of Defense for International Security Affairs and of the Deputy Senior Advisor to Under Secretary of War for Policy Elbridge Colby. She also spent an extensive tenure on Capitol Hill as National Security Advisor to Senator Mike Lee, R-Utah.