SEOUL, South Korea — A Korean American detained for six months in North Korea has been sentenced to 15 years of hard labor for "hostile acts" against the state, the North's media said Thursday — a move that could trigger a visit by a high-profile American if history is any guide. Kenneth Bae, 44, a Washington state man described by friends as a devout Christian and a tour operator, is at least the sixth American detained in North Korea since 2009. The others eventually were deported or released without serving out their terms, some after trips to Pyongyang by prominent Americans, including former U.S. presidents Bill Clinton and Jimmy Carter.