U.S. Democratic presidential candidate Barack Obama denounces his preacher's racially-charged sermons, but says he cannot disown him, in a speech urging Americans to move past racial division. U.S. Democratic presidential candidate Barack Obama denounced his preacher's racially-charged sermons, but says he cannot disown him, in a speech urging Americans to move past racial division in Philadelphia on Tuesday (March 18). Obama sought to quell a political firestorm ignited when news outlets called attention to sermons by the Rev. Jeremiah Wright at Trinity United Church of Christ in Chicago, which the Illinois senator attended for two decades. Wright, who retired recently, has railed that the Sept. 11 attacks were retribution for U.S. foreign policy, called the U.S. government the source of the AIDS virus and expressed anger over what he called racist America. "We bombed Hiroshima, we bombed Nagasaki, and we nuked far more than the thousands in New York and the Pentagon, and we never...