Republicans who disagree with my stance make the following argument: Mr. Trump, while flawed, is preferable to Hillary Clinton. His cabinet appointments, they say, have been reassuring, and it’s true that several of them are. In addition, the nominee to replace Antonin Scalia on the Supreme Court is certain to be more of an originalist than a Clinton appointment would be. On top of that, Republicans are in control of Congress, meaning they are likely to drive much of the agenda, particularly given Mr. Trump’s notable lack of interest in policy. Whatever misgivings anti-Trump conservatives might have had about him, he’ll undo much of the agenda of his liberal predecessor while Mrs. Clinton would have built on it.