Who made the policy of containment?

The policy of containment was primarily developed by U.S. diplomat George F. Kennan in the late 1940s. It aimed to prevent the spread of communism during the Cold War by containing Soviet influence and power. Kennan's ideas were articulated in his "Long Telegram" and later in an article published in 1947 under the pseudonym "X." The policy became a cornerstone of U.S. foreign policy throughout the Cold War.