What idea would the U. S. use to justify intervention in the Vietnam War?

They would use anti-communism and the domino theory propaganda to justify genocide (like the Mai Lai massacre)

China had become communist in 1949 and communists were in control of North Vietnam. The USA was afraid that communism would spread to South Vietnam and then the rest of Asia. It decided to send money, supplies and military advisers to help the South Vietnamese Government.

Explanation:

considered the turning point in pacific war. the japanese tried to lure the american navy out so it could be destroyed but failed. the americans were led by admiral chester nimitz. the victory by america would put them on the offensive for the remainder of the war.

besides the fact that abraham lincoln abolished slavery, and greatly benefit black people, he had a heavy impact of the definition of what democracy was, and should be.