On June 25, 1950, on both sides of the Pacific Ocean, Mao Zedong, the leader of the new China, and US President Harry Truman, who were thousands of miles apart, received an urgent report almost at the same time. What Truman and Mao Zedong learned was the same news - the outbreak of the Korean War.

This episode mainly introduces the international background before and after the outbreak of the Korean War in 1950, as well as the reactions and responses of the top decision-makers of China and the United States after learning of the outbreak of the war. When the United States began its armed intervention in the Korean Civil War, it linked the North Korean issue with China's sovereign dignity. In the face of the U.S. encroachment on China's sovereignty, Mao Zedong and the Party Central Committee took precautions, adjusted their strategic deployment in a timely manner, established the Northeast Frontier Defense Force, and firmly grasped the strategic initiative.