As  long as the United States has existed, it has maintained complex and important diplomatic and military ties with Europe. Since the second world war, these ties have become increasingly important to the broader security of the world. Arguably the most important is the North Atlantic Treaty Organization (NATO), which began on April 4th, 1949 with the signing of the North Atlantic Treaty in Washington DC. The premise of NATO was simple: the signatories would form an alliance, one that would bring their forces together in military exercises and on the battlefield. If one member was attacked, the other members pledged to come to their defense by any means necessary. The organization would be responsible for European security and stability as well as ensure that no single power dominated Europe.  After two bloody wars against aggressive, expansive military powers and the spectre of a third, the United States realized that European interests were increasingly American interests.

The rise of the Soviet Union, eerily similar to the beginnings of the last two European conflicts, alarmed the United States. In response, the United States offered major economic gifts to European countries, drawing them away from the lure of communism with the Marshall plan and Truman doctrine. To protect itself and its European allies, the United States pushed for more than just economic relations and individual alliances. The United States was ready to unite the North Atlantic, building a buffer to the Soviet Union and developing a dominant global military force that could keep peace and help the world move in a democratic direction. In the battle against communism and extremism, the United States no longer stood alone.

The NATO alliance become even more critical to American and European security as the cold war intensified. During the cold war, the United States brought NATO under its nuclear umbrella, committing to using nuclear weapons to retaliate against a nuclear strike on a NATO country. With this agreement, European NATO members made their homes potential battlefields in the hope of deterring Soviet aggression. This alliance was built on trust in every other country’s promise to come to one’s aid. That trust proved to be founded. The United States has been ever present in European security, and European members have reciprocated that loyalty. In the aftermath of 9/11, NATO upheld its promise to treat an attack on one as an attack on all by following the United States into the war in Afghanistan with a joint security force with troops from 42 countries.

Even with this history of success and collaboration, cracks are starting to appear in NATO’s united front. The current administration has begun a loud debate on burden sharing, arguing that European countries have not paid their fair share to the alliance, and publicly questioning whether they should provide the same support to NATO in the face of this perceived inequality. While the US contributes 22% of NATO’s budget, the United States’ GDP is more than half of the total GDP of the alliance. European countries also contribute more manpower and military equipment to the alliance than the United States. NATO guarantees both European security and American influence in Europe. Given those dual benefits, the alliance represents a comparative bargain to the United States.

Additionally, NATO guidelines apply to the defense budget of each country. NATO burden sharing is not solely centered on the money provided to the alliance. More importantly, the alliance sets an ideal amount of domestic defense spending. European countries are expected to contribute 2% of their GDP to defense and the United States 3%. While it is true that many European countries fall short of their expected contribution and that United States spends far more, it is important to remember that when the US spends on its defense, its budget is divided all over the world. In contrast, the defense budget of European countries mostly goes to military actions within Europe. Europe is hardly shirking its responsibilities.

These conversations on burden sharing are nothing new, as the United States has been pushing other members to increase their defense spending from the beginning of NATO. Though the broader conversation on burden sharing has not changed, the United States increasingly treats the alliance as a zero-sum game. NATO was a revolutionary type of alliance and its continued survival points to its members’ faith in the organization. The steady faith and devotion of its members allows NATO to survive as a complex coalition of many different countries with many different agendas. To ensure the survival of NATO, this commitment needs to continue across the board, especially in the United States.

American support is crucial to NATO. Continuing hints of insincerity on the American side and implications that European security alone is not enough to justify American contributions have rattled the continent and pushed Europeans away. If Europeans begin to believe that they can no longer count on America, they will no longer feel the need to consider American interests. European countries are now talking about increasing their military capabilities and becoming more independent from the United States. An unstable Europe would cost the United States far more than any perceived losses from their investments in NATO.