"Over a period of three years or so, we killed off — what — 20 percent of the population," Air Force Gen. Curtis LeMay, head of the Strategic Air Command during the Korean War, told the Office of Air Force History in 1984. Dean Rusk, a supporter of the war and later secretary of state, said the United States bombed "everything that moved in North Korea, every brick standing on top of another." After running low on urban targets, U.S. bombers destroyed hydroelectric and irrigation dams in the later stages of the war, flooding farmland and destroying crops.