Boris Berezovsky and other Kremlin critics took out a full-page advertisement in major U.S. newspapers on Tuesday warning the United States not to trust President Vladimir Putin. The advertisement in The Washington Post, New York Times and Wall Street Journal was clearly designed to embarrass Putin as he headed for the United States to attend the UN General Assembly and a summit with U.S. President George W. Bush. Titled "Seven questions to President George Bush about his friend President Vladimir Putin," it accused Putin of undermining democracy, stamping his control on parliament, courts and media, and overseeing genocide in Chechnya....