Dick Cheney eviscerated Donald Trump as the greatest threat to the United States in history in a new campaign ad for his daughter, Rep. Liz Cheney, who is facing a defeat in the Republican primary in Wyoming next week. 'In our nation's 246 year history there has never been an individual who is a greater threat to our Republic than Donald Trump,' veteran Republican Cheney said in a new clip released on Thursday. The congresswoman brought out her 81-year-old former vice president father as a last ditch effort to defy recent polling that puts her squarely behind primary rival Harriet...