North Atlantic Treaty

The North Atlantic Treaty created a peacetime military alliance linking the United States, Canada, and ten Western European countries. Its collective-defense commitment made an attack on any member a matter for all, marking a decisive departure from the United States’ peacetime tradition and one of the major achievements of Harry S. Truman’s presidency.

Place in Postwar Policy

In a January address outlining four proposals for American policy, Truman called for continued support of the United Nations, sustained backing for the Marshall Plan, and a new defense arrangement among the freedom-loving nations of the North Atlantic. He presented the alliance as part of a wider effort to support recovery and deter armed attack, rather than as an isolated military measure.

Negotiation and Commitment

The treaty followed hard negotiations in which Secretary of State Dean Acheson did much of the detailed work. Truman supplied the political commitment: after his November election victory, he instructed the State Department to open negotiations for the alliance. Although Acheson and British Foreign Secretary Ernest Bevin carried out much of the negotiation, Truman regarded the resulting agreement as his treaty and described its signing as a historical milestone.

Ratification and Significance

The agreement was the first peacetime military alliance formed by the United States since the signing of the Constitution. Truman believed that comparable collective-security arrangements in 1914 and 1939 could have spared the world two terrible wars. Despite expectations of fierce opposition from conservative Republicans in the Senate, resistance proved milder than anticipated. On July 21, 1949, the Senate approved ratification by 82 votes to 13. The treaty’s establishment, alongside the success of the Berlin Airlift and the prospect of a prosperous, self-governing West Germany within the Western Alliance, contributed to a markedly more favorable atmosphere for Truman. He ranked the treaty with the Marshall Plan among the proudest achievements of his presidency and was confident that its importance would become clearer with time.