MOSCOW, Aug 17 (Reuters) - Mikhail Gorbachev, the leader who oversaw the withdrawal of Soviet forces from Afghanistan in 1989 after Moscow"s failed decade-long campaign there, said on Tuesday that NATO"s own deployment to the country had been doomed from the start. Gorbachev, 90, regarded the Soviet presence in Afghanistan as a political mistake that was sapping precious resources at a time when the Soviet Union was living through what turned out to be the twilight of its own existence. The Soviet-backed authorities in Afghanistan survived for three years after the withdrawal by Moscow of its main forces but never recovered from a Russian decision to cut aid to them after the Soviet collapse in January 1992 and fell later that year. Gorbachev was cited by Russia"s RIA news agency as saying that NATO and the Americans had no chance of success and had badly mishandled their own Afghan campaign. "They (NATO and the United States) should have admitted failure earlier. The important thing now is to draw the lessons from what happened and make sure that similar mistakes are not repeated," Gorbachev told RIA. "It (the U.S. campaign) was a failed enterprise from the start even though Russia supported it during the first stages," he added. "Like many other similar projects at its heart lay the exaggeration of a threat and poorly defined geopolitical ideas. To that were added unrealistic attempts to democratise a society made up of many tribes."