Question

vietnam was divided at the 17th parallel into communist north and non - communist south vietnam. the united states used the to justify its intervention in southeast asia. the united states helped cr , which was designed to be a military alliance to prevent the spread of communism. options: korean war, domino theory, arms race

Explanation:

To determine the correct term for justifying US intervention in Southeast Asia, we analyze the options:

• "Korean War" was a conflict in Korea, not a justification for Southeast Asia intervention.
• "Domino theory" posited that if one country fell to communism, neighboring ones would too, which was used to justify US involvement in Vietnam/Southeast Asia to stop communist spread.
• "Arms race" refers to competing military buildup (like US - USSR), not related to Southeast Asia intervention justification. So "domino theory" is correct.

Answer:

domino theory