PHNOM PENH, Cambodia—When United Nations peacekeepers entered Cambodia in 1992, their $3 billion mission aimed to remold a nation traumatized by war and genocide and set it on a course to democracy.
U.N.-sponsored elections the next year failed to dislodge Prime Minister Hun Sen, who had been installed eight years earlier. The leader, diplomats say, convinced the U.S. and other donors that he was nudging Cambodia toward democratic rule.
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