What ideology did the Truman Doctrine primarily counter?

The Truman Doctrine primarily countered communism, which emerged as a significant threat to democracy and capitalism after World War II. Announced in 1947, the doctrine established a U.S. policy to provide political, military, and economic assistance to countries resisting communist influence. This was largely in response to the expansionist policies of the Soviet Union, which sought to spread communism globally. The Truman Doctrine underscored the U.S. commitment to contain communism and support free peoples who were defending their democracies against totalitarian regimes. This ideological confrontation marked the beginning of a more active U.S. role in global politics, particularly during the Cold War, as it aimed to prevent further Soviet expansion.

The other ideologies presented in the choices do not capture the primary focus of the Truman Doctrine. While fascism, monarchism, and socialism were relevant discussions in various contexts, the specific aim of this doctrine was centered on countering the spread of communism and its influence during a time of growing tensions between the U.S. and the Soviet Union.