"Before the invasion, Korea was not included in the strategic Asian Defense Perimeter outlined by Secretary of State Acheson. Military strategists were more concerned with the security of Europe against the Soviet Union than East Asia......
.....On January l2, 1950, Secretary of State Acheson had even announced publicly that the American "defensive perimeter" did not extend to South Korea.
Stalin read the speech carefully—as well as (courtesy of British spies) the top-secret National Security Council study upon which it was based—and authorized Ills foreign minister, Molotov, to discuss it with Mao Zedong. The Soviet leader then informed Kim Il-sung that according to information coming from the United States, . . . the prevailing mood is not to interfere." Kim in turn assured Stalin that "the attack will be swift and the war will he won in three days."