A US sixth aircraft carrier and B-2 stealth bombers have been ordered to deploy as part of the unrelenting US military buildup against Iraq, officials said amid proliferating signs that war is rapidly approaching.Iraq's elite Republican Guards were on the move inside Iraq, apparently to shore up the regime's defenses in the Sunni heartland, according to US officials, who spoke on condition of anonymity.US forces in the Gulf region and the eastern Mediterranean swelled to 225,000 this week, including 111,000 in Kuwait, where US soldiers and marines have been staging for a possible invasion, a US defense official said,...