Michael Cohen once said he would take a bullet for Donald Trump. But on Thursday, Trump was on felony charges based largely on the onetime loyal fixer's testimony against his former boss. Over four days earlier this month, Cohen took the witness stand as the star prosecution witness in the first-ever criminal trial of a US president, past or present. He testified that Trump directed him to pay off a porn star before the 2016 election, and then approved a plan to falsify business records to cover it up. The testimony in New York state court in Manhattan marked the...