In the1960’s, the United States was involved in Vietnam primary because:(1 point) Responses it feared that if Vietnam became communist there would be a domino effect causing surrounding countries to become communist. it feared that if Vietnam became communist there would be a domino effect causing surrounding countries to become communist. American businesses in Vietnam supported Communist control. American businesses in Vietnam supported Communist control. the American people supported the involvement in Vietnam. the American people supported the involvement in Vietnam. Cambodia was threatened militarily by the possibility of a Communist government in Vietnam.

The primary reason for the United States' involvement in Vietnam in the 1960s was the fear of a domino effect. The US government feared that if Vietnam became communist, it would lead to the spread of communism to other surrounding countries. Furthermore, the threat of communism in Cambodia was also a concern for the US as it could lead to military threats. American businesses in Vietnam did not support Communist control, and while there was some support from the American people for the involvement in Vietnam, it was not the primary reason for the US government's decision.