A communist state occupying the northern half of the Korean peninsula. After World War II, Korea was occupied from Japan, with U.S. forces holding the southern half of the country. Soviet troops occupied the north. In 1948, this partition was made permanent, and separate regimes were established in the two zones. The Democratic People's Republic of Korea was established on May 1, 1948, under the leadership of Kim Il Sung. In 1950, North Korea attacked South Korea, but three years of fighting, with United States, United Nations and Chinese intervention, ended with a cease-fire that left the boundary between the two Koreas essentially unchanged. The greatest part of Korea's resources and prewar industry were in the north, and the North Korean government has actively developed these into a substantial industrial plant. North Korea is one of the last truly totalitarian states, built upon a personality cult centered around Kim Il Sung, a cult that has been maintained, though with some difficulty, in his son, Kim Jong Il, who succeeded his father in 1994. The regime's xenophobic foreign policy and chronic economic mismanagement have brought famine internally and largely isolated its dealings abroad. It continues to support a large military force and to develop nuclear weapons, so its increasing instability is grounds for grave concern. North Korean stamp issues are subject to U.S. Treasury Department restrictions and cannot be imported through the mail.