A crowd gathers around an APC as others climb aboard the vehicle and try to block its advance near Red Square in downtown Moscow, Monday, Aug. 19, 1991. The August 1991 hard-line communist attempt to overthrow the reformist Gorbachev was an attempt to keep the Soviet Union from disintegrating, the organizers said. But it backfired and precipitated the end of the USSR, which collapsed four months later. (AP Photo/Boris Yurchenko)