The United States fought in the Vietnam War to prevent the spread of communism.
This was part of the domino theory of a wider containment policy , with the stated aim of stopping the spread of communism worldwide .	domino theory	domino theory	containment policy	containment policy
It is best known as the Cold War policy of the United States and its allies to prevent the spread of communism .	communism	communism	Cold War	Cold War
