Donald Trump, currently falling in the polls for the GOP nomination (currently 3rd now in Iowa), refuses to acknowledge he has no proof to backup his claim that on 9/11 he saw "thousands and thousands" of Muslims in New Jersey cheering at the World Trade Center being attacked.
At least Chuck Todd tries here to get a real answer from Trump: “You’re running for President of the United States! Your words matter! Truthfulness matters! Fact-based stuff matters!”