Michael Cohen’s first day on the witness stand in Donald Trump’s Manhattan trial gave us scores of incriminating details — many with spice about things not so nice.  The underlying purpose for prosecutors was methodical — to rebut the defenses that Trump’s lawyers would raise and to fill any gaps in prosecutors’ evidence. Throughout Monday, Cohen’s testimony went to the heart of the case. He told jurors that Trump participated in a meeting in Trump Tower in mid-January 2017, when he...