By David Gutman WHITE SULPHUR SPRINGS, W.Va. - Former Vice President Dick Cheney warned in ominous tones of a weakened American military and a coming attack on America during a speech to the West Virginia Chamber of Commerce on Thursday, part of a recent media tour to promote his new book.Cheney and his daughter Liz Cheney, who co-wrote the book "Exceptional," spoke about the growing threats they see in the world and "why it is uniquely America's duty to be freedom's defender.""Consider a world in which we don't lead," said Liz Cheney, who served in President George W.