The Korean War was an armed conflict between North Korea (with the support of China and the Soviet Union) and South Korea (with the support of the United Nations, principally from the United States). The war began on June 25, 1950 when North Korea invaded South Korea following clashes along the border and insurrections in the south. The war unofficially ended on July 27, 1953 in an armistice.
The war was when North Korea invaded its southern counterpart, intending to unify the Korean Peninsula. However, he Korean War ended with a stalemate with the establishment of the Korean Demilitarized Zone with the U.S occupying the buffer zone in favor of South Korea. Since then, tensions between the two nations were high.
The Korean War radicalized Kang Yeonsak to the point of Korean unification after the death of his parents and supposed "justice" for his country. Kang would then go on to become the founder of a terrorist organization called the Koreans for United Freedom, with the ultimate goal to capture the White House and force the U.S to withdraw from the Korean Demilitarized Zone and allow a North Korean invasion of South Korea.
Though he almost succeeded with his plans, he was defeated by former Army Ranger turned Secret Service agent Mike Banning, who took out the remaining K.U.F. and killed Kang after a brutal fight.