Assuming your question is in reference to the Vietnam War, the United States got involved because of
<h2>domino theory and the policy of containment.</h2>
"Domino theory" was applied in justifying US involvement in the Vietnam War. Domino theory said that the spread of communism in Vietnam would result in other countries in the region falling like dominoes to the influence of communism.
Domino theory was a corollary to the overall policy of containment that developed as the United States' policy regarding communism after the end of World War II. George F. Kennan is known for recommending the policy of containment, which said that the best way to deal with the threat of communism was simply to try to keep it contained to the places where it already existed.
He showed that the people were not as free to conduct whatever deeds they wanted and that the federal government was still in charge and that laws would have to be obeyed or people would be punished if they broke the laws. He also showed that the government will only meddle in such affairs reasonably and not be tyrannical.
This was shown through active confrontation with the people who thought they could do what they wanted. For example, during the progressive age Roosevelt engaged in breaking monopolies and trusts which didn't include physical violence but did include breaking unjust treatment of the country and exploitation of laws.
The right to home ownership
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