Which theory argues that if one country falls to communism, neighboring countries will follow?

Which theory argues that if one country falls to communism, neighboring countries will follow?

• A. Domino Theory
• B. Interstate Highway Act
• C. Launch of Sputnik
• D. Bay of Pigs

Answer: (A)

The idea being tested is the domino effect—the belief that if one country falls to communism, neighboring countries are likely to follow. During the Cold War, this worry shaped U.S. foreign policy and helped justify actions aimed at containing communism to prevent it from spreading region by region. Proponents argued that a single country turning communist could destabilize nearby nations, creating a ripple effect that threatened broader regional security. That’s why this term fits best: it directly captures the fear of rapid, sequential spread of communism. The other options don’t describe a theory about how political systems spread. The Interstate Highway Act is about building roads, not geopolitics. The launch of Sputnik relates to the space race and technological competition. The Bay of Pigs was a specific event, not a theory about how influence spreads.

The idea being tested is the domino effect—the belief that if one country falls to communism, neighboring countries are likely to follow. During the Cold War, this worry shaped U.S. foreign policy and helped justify actions aimed at containing communism to prevent it from spreading region by region. Proponents argued that a single country turning communist could destabilize nearby nations, creating a ripple effect that threatened broader regional security.

That’s why this term fits best: it directly captures the fear of rapid, sequential spread of communism. The other options don’t describe a theory about how political systems spread. The Interstate Highway Act is about building roads, not geopolitics. The launch of Sputnik relates to the space race and technological competition. The Bay of Pigs was a specific event, not a theory about how influence spreads.