NEW YORK – Four years ago when he first moderated a general election presidential debate, Chris Wallace was firm and funny in trying to get Donald Trump and Hillary Clinton to stop talking simultaneously. Wallace declined an interview request through Fox but his work offers clues about how he will approach the assignment. Trump has tweeted, more than once, that Chris will “never be his father.”Mike Wallace, it should be noted, never moderated a presidential debate. During interviews with Trump this summer, Wallace and Jonathan Swan of Axios proved particularly adept at challenging presidential misstatements. “I do not believe it is my job to be a truth squad,” Wallace told a Fox News colleague before the 2016 debate.