With the Soviets boycotting the UN Security Council because the Americans the refused the entry of Communist China) the United Nations, supported by the United States, freely passed a resolution requesting military action against North Korea. Led by General Douglas MacArthur, the UN Forces arrived along with the US Forces on July 1, 1950. Truman believed that the North Korean atomic threat was "a threat based on contingency planning to use the bomb, rather than the faux pas so many assume it to be" and so did not use brinkmanship but also continuously opted for limited war. His beliefs in ceasefire and peacekeeping between the North and the South were cause for great conflict with MacArthur, who sought total war. MacArthur believed that the United States should take the opportunity to wipe out communism permanently before it grew stronger by using all of its weapons such as turning the war into nuclear war. MacArthur was dismissed as a result of his continuous defiance to Truman and other superiors on April 11, 1951, after he sent an ultimatum to the Chinese Army without consent of Truman.