Why did nort korea cross the 38th parallel and invade south korea?
Rhee and Kim competed to reunite the peninsula, with each of them using military attacks along the border throughout 1949 and early 1950.[30][31] Although Kim and his close associates believed in unifying Korea by force, Stalin was reluctant to embark on a course that might provoke a war with the United States.[32] On January 12, 1950, United States Secretary of State Dean Acheson gave a speech declaring that America’s Pacific defense perimeter was made up of the Aleutians, Ryukyu, Japan, and the Philippines, implying that America might not fight over Korea. Acheson said Korea’s defense would be the responsibility of the United Nations.[33] In mid 1949, Kim Il-Sung pressed his case with Joseph Stalin that the time had come for a reunification of the Korean Peninsula. Kim needed Soviet support to successfully execute an offensive far across a rugged, mountainous peninsula. Stalin, however refused support, concerned with the relative lack of preparedness of the North Korean armed forces
