When former President Donald Trump was in office, a number of his aides said they wanted to quit out of concern for the country's political and military future. Some did quit, some didn't. Political reporters Susan Glasser and Peter Baker conducted 300 interviews for their new book The Divider – two of those with the former President himself. They spoke to Ayesha Rascoe about Trump's White House tenure – and what it means for the American presidency at large.