Answer :
Final answer:
The Domino Theory states that the spread of communism in one country would lead to neighboring countries following suit, influencing U.S. foreign policy during the Cold War era.
Explanation:
The Domino Theory in the Context of Cold War Policies
Domino theory refers to the belief that the spread of communism in one country would lead to neighboring countries also becoming communist. This theory influenced U.S. foreign policy, particularly in Southeast Asia, during the Cold War era. For example, President Eisenhower used the domino theory to justify American involvement in Vietnam to prevent the spread of communism.