Opposition to United States involvement in the Vietnam War With no clear sign of victory in Vietnam, American military casualties helped stimulate opposition to the war by Americans. In their book "Manufacturing Consent", Noam Chomsky and Edward Herman challenge that traditional view of how the media influenced the war and propose that the media instead censored the more brutal images of the fighting and the death of millions of innocent people. The U.S. became polarized over the war. Many supporters of U.S. involvement argued for what was known as the domino theory, a theory that believed if one country fell to communism, then the bordering countries would be sure
Non-intervention in the Spanish Civil War follow a policy of non-intervention, but did not announce it officially. This isolationism on the Spanish war would later be identified as disastrous by Under-Secretary of State Sumner Welles. Five days later, the Glenn L. Martin Company enquired whether the government would allow the sale of eight bombers to the Spanish Republican Air Force; the response was negative. It also confirmed it would not take part in several mediation attempts, including one by the Organization of American States. Mexico soon became the first nation to openly support the Republicans. On 15 August, the United Kingdom banned exports of war material