Donald Trump was promising to destroy a vile criminal cartel. Unfortunately, not his own. But one could be forgiven for mistaking the vicious tactics of the MS-13 gang, as described by the president in a Long Island speech on Friday, with those of the Trump White House. “They don’t like shooting people because it’s too quick, it’s too fast,” Trump said, adding: “They like to knife them and cut them, and let them die slowly because that way, it’s more painful, and they enjoy watching that much more. These are animals.” The president could have been describing his own sadistic...