(FILES) US Democratic presidential candidate Hillary Clinton and US Republican presidential candidate Donald Trump shakes hands after the second presidential debate at Washington University in St. Louis, Missouri, on October 9, 2016. From Gerald Ford's catastrophic Soviet gaffe to Ronald Reagan's witty remark about his age and Joe Biden's infamous implosion, US presidential debates have been jaw-dropping in every sense of the word. (Photo by Robyn Beck / AFP) (Photo by ROBYN BECK/AFP via Getty Images)