For over a century, American national security strategy firmly depended on a transatlantic foundation.  Since Woodrow Wilson’s decision in 1917 to send U.S. troops to fight in World War I, our core geostrategic principle has been that no hostile power should be permitted to dominate the resources of Europe and Western Eurasia.

The logic was compelling. Such dominance, should it emerge, would trap the United States in the Western Hemisphere, thereby blocking its ability to project power across the World Ocean and to access vital trade routes and natural resources essential to the nation’s prosperity and homeland security. The same reasoning led the administration of Franklin Delano Roosevelt to prioritize Europe over Asia during World War II, even though it was Japan that directly attacked the United States. It was the same geostrategic principle that, having vanquished Germany, induced America to commit itself to the defense of Europe against the Soviet Union and led to the establishment of the North Atlantic Treaty Organization.

For half a century, the United States stood guard on the front lines of divided Germany, containing Soviet expansionism and, ultimately, contributing to the collapse of the Warsaw Pact and the liberation of Central and Eastern Europe and the Baltic States. During both World Wars and throughout the Cold War, American strategists understood this simple truth: a hostile power controlling Europe would possess the industrial capacity, population, and geographic position to threaten the U.S. directly. This understanding influenced U.S. involvement in World War I, the “Germany First” strategy in World War II, and the shaping of NATO’s structure and forward bases after 1945.

The United States established itself as a global power by first securing its immediate neighborhood in the Americas and then preventing any hostile power from controlling Europe and, by extension, the Atlantic routes to the Western Hemisphere. Despite pressures within the U.S. policy community after the Cold War to focus more on Asia – a strategy first voiced by Barack Obama in late 2011 and one that has gained supporters over the past decade – securing Europe remains vital today. In fact, the resurgence of great-power conflicts, the weakening of institutional structures, and the return of large-scale continental warfare in Eastern Europe have only heightened the importance of this strategy.

Today’s strategic discussion often views the Pacific as the main theater and Europe as a secondary, stabilizing front. While this shift may seem natural, it is misleading. It assumes that China is the only peer competitor capable of reshaping the global order; that geography in Asia is crucial, whereas in Europe it is less significant; and that the Atlantic alliance is fixed, requiring only maintenance instead of being a strategic priority. Each of these assumptions misses the mark. An Atlantic-first strategy—one that makes Europe the focus of American grand strategy—better protects the homeland, maintains the industrial and technological foundations of American power, and supports the alliance structure that enables U.S. global leadership.

The Pacific is indeed important. But America’s ability to compete effectively there first depends on ensuring that Europe and the Atlantic are secure. As the scholars Wess Mitchell and Jakub Grygiel have argued, “Europe is the United States’ indispensable base in global geopolitics.”[1] This is true in terms of geostrategy, trade and investment flows, credibility, and political culture.

Indeed, Europe remains the world’s largest hub of advanced industrial economies outside North America. It spans the sea lanes and air routes that connect the United States to the rest of the world. The Atlantic remains the shortest and most secure communication line between the U.S. and its key allies, providing a pathway to project power into the Arctic, the High North, the Middle East, and Africa. Most importantly, Europe has the necessary material resources and manpower to serve as the core of NATO’s conventional deterrence and defense, with the United States offering the nuclear umbrella, high-end enablers, and logistical support. In short, the challenge for U.S. strategy in Europe is not to disconnect the Atlantic from the Pacific but to organize cooperation within NATO in a way that reduces costs while restoring deterrence and maintaining American influence on the continent.

Europe should remain a top priority because the United States is currently facing not just one major power adversary but an “Axis of Dictatorships,” including China, Russia, North Korea, and Iran. Since taking office, Vladimir Putin has been challenging the settlement that ended the Cold War, aiming to restore imperial greatness by reducing American influence in Europe and negotiating spheres-of-influence arrangements with key European powers. A revanchist Russia, supported by China’s economic strength and Iranian and North Korean backing, is trying to reshape the European security order through force.

If Moscow succeeds in coercing or splitting Europe’s eastern NATO flank, the repercussions will go far beyond Ukraine or the Baltic region. It could lead to the first successful breach of the post-1945 security framework in Europe and signal to allies worldwide that American security guarantees are no longer credible. Such a development would have significant ripple effects in the Pacific and other regions, raising doubts about the U.S. security commitments and its overall resilience. Indeed, Beijing is closely watching NATO’s actions in Europe to gauge how the U.S. and its allies would respond in Asia. If the transatlantic alliance weakens or fractures altogether, China will likely interpret this as a green light to intensify pressure on Taiwan and to gain regional influence. Conversely, if the transatlantic alliance remains strong, China must reckon with a united democratic coalition that shows clear resolve.

The Pacific and the Atlantic are two very different theaters, each hosting distinct potential kinetic conflicts. The Pacific involves a long-distance maritime struggle across blue waters, while Europe features a close-quarters continental fight near Atlantic approaches. To understand the scale, projecting power across the Pacific requires the U.S. Navy to manage the “tyranny of distance.” In contrast, Europe’s distances are much shorter — it is only 20 miles from the Belarusian border to Vilnius, Lithuania’s capital, and just 130 miles from its border to Warsaw. In brief, securing the Atlantic has immediate implications for defending the American homeland, as shown by the recent dispute between the Trump administration and NATO allies over Greenland.

The problem confronted by NATO today is the three-decade-long “vacation from history” that Europe has taken, whereby – except for the countries in the Northeast Corridor (i.e., Norway, Sweden, Finland, the Baltic States, and Poland) – the continent has effectively disarmed. Still, no theater in the world offers the United States the density of capable, interoperable, technologically advanced allies that Europe does and, provided they move with alacrity to resource their defenses, would allow America to transfer the burden of the conventional defense of Europe to its allies. Alliances serve as force multipliers, and a secure Europe frees up American resources. The NATO alliance is more than just a network of transactional partnerships; it is a deeply institutionalized military alliance that has evolved over 75 years through shared planning, logistics, intelligence sharing, and industrial cooperation. No similar structure exists in the Pacific, as U.S. alliances there are primarily bilateral and geographically dispersed.

Alliances are fundamentally built on shared threats and interests, but shared values help strengthen them and make them more effective during crises. European democracies remain America’s closest political allies, with a shared history and the common roots of our political institutions and culture. Public support for alliance cooperation, sanctions, and collective defense—although reduced by recent tensions in transatlantic relations—is still generally higher in Europe than in any other region.[2]

This transatlantic political alignment allows for a consistent strategy across U.S. administrations. Conversely, Indo-Pacific politics are diverse and often cautious. Many regional powers in Asia simultaneously balance relations with China and the United States, making complete alignment in a prolonged confrontation unlikely. In short, a U.S. strategy focused on Europe will leverage the most politically reliable coalition available to the United States. To get there, Washington must continue pressing European capitals to meet their pledge to spend 5% of GDP on defense by 2035, and it should keep reforming its approach to working with NATO allies, with a renewed focus on the Northeast Corridor, which has become the new center of gravity for the alliance after Sweden and Finland’s accession to NATO. But if American strategy shifts away from Europe, it risks weakening the most developed alliance system in history at a crucial moment when cohesion offers a decisive edge in great-power competition and conflict.

Supporting this system isn’t just a sentimental attachment to legacy institutions. It’s a strategic necessity. Every European brigade, frigate, air wing, and cyber unit that contributes to collective defense reduces the burden on U.S. forces worldwide. Although it will likely take Germany and other Western European nations around a decade to rebuild their neglected military capabilities, Europe has the industrial capacity to move swiftly and take on the primary role in NATO’s conventional deterrence and defense. The European allies possess the financial resources to accelerate rearmament efforts.

The temptation to focus on the Pacific instead of the Atlantic, or even to declare the Pacific as the overarching priority, is understandable. China is rising, Taiwan is vulnerable, and the Indo-Pacific is changing fast. But our national security strategy must involve clearly defining and prioritizing national interests. It’s about protecting the core sources of power that make all other U.S. efforts possible. Europe is that foundation, as a strong NATO provides the industrial strength, alliance unity, geographic advantage, and political legitimacy that support America’s global strategy. Without Europe, the U.S. faces the Pacific challenge with fewer allies, weaker logistics, and higher strategic risks.

Prioritizing Europe, therefore, is not nostalgia. It is strategic realism. The Atlantic remains the key artery of American power, and Europe continues to be America’s essential partner. The U.S. strategy for Europe should focus on enabling allies to assume greater responsibility for their defense by providing the resources required to implement the capabilities outlined in NATO’s regional plans. We should also leverage Europe’s industrial capacity through defense-industrial base integration, thereby boosting NATO’s ability to produce weapons and munitions quickly and at scale. Improving stability in the European theater through continued U.S. presence and with greater contributions from allies will allow the United States to focus on projecting power in the Pacific to ensure the ongoing prosperity and security of the American Republic.

The Atlantic and the Pacific are not an either/or proposition. They are one problem set, and should be treated as such.