The domino theory was used from the 1950's through the 1980's in the US to justify various military engagement, most notably in the Korean and Vietnam Wars. The concern was that if communist regimes in North Korea and North Vietnam completely took over their respective countries, they would spread throughout south-east Asia.
President Dwight D. Eisenhower continued Harry Truman's support for the French in Vietnam because he believed in the domino theory. The domino theory suggested that if one country fell to communism, neighboring countries would also follow. To prevent the spread of communism in Southeast Asia, Eisenhower believed it was necessary to support the French in their fight against the communist-led Viet Minh.
The Growth of communism The domino theory The cold war The French loosing control of Vietnam (the French were an ally of the American) The belief that communism was an international conspiracy
Vietnam
American invlovement in Vietnam, which escalated into full-scale war, began with an American political idea called the "domino theory." This concept of foreign relations, now discredited, posited that the spread of Communism must be stopped in Vietnam or it would spread to all the neighboring countries and eventually dominate the world.
The Vietnam war
fascism
it temporaily stopped spread of communism but it annoyed the soviets
It happened during the cold war because people were scared of communism and its spread across the world. The theme of the cold war was the prevention of the spread of communism, and many people thought that communism was spreading inside the US. The US was extremely paranoid about communism, which led to its involvement in Vietnam and many other wars. In a nut shell, Americans were so paranoid that they thought communism was spreading in their own country.
D. The revolution would be led by a small group of hard-core dedicated revolutionaries ;)
We engaged communist forces in the Korean and Vietnam wars which also led to the downfall of the soviet union
Assuming that you mean Korea and Vietnam respectively, US foreign policy was dominated by two political theories: the Containment Policy and the Domino Theory, The first one, formulated in the late Forties after the Communist takeover of China and a number of East European countries, said that Communism should be contained in the territories it now controlled and that any effort to expand them further should be forcibly resisted. The second held that if one country in Asia would further fall to Communism, all other countries in the region would fall to it like so many Domino's. This policy therefore logically led first to the Korean war and later to the Vietnam war. The first one was succesful, the second one was not. On the other hand, the Domino Theory was proven wrong.
Considering how he led an armed revolution to install a "communist" government in China, he appears to be pro-use of force.