New Jersey Gov. Chris Christie's aides deliberately induced a big traffic jam as revenge against a mayor who wouldn't endorse him. Christie denies that he was aware they were doing this. Let's suppose, just for the sake of argument, that Christie's telling the truth. Does that get the governor—and would-be president—off the hook?

Not necessarily. Marc Ambinder explains why, leading off with the portrait of Christie in the recent book Double Down:

Double Down's Christie was megalomaniacal, self-possessed, and obsessed with reciprocity: You do well by him, and he'll do well by you. You fundraise without his permission in New Jersey, and he'll cut the donors off. Loyalty trumped all. If Christie perceived you as disloyal, you were out of his inner circle. That's in passive voice because Christie would leave it to his lieutenants to enforce this code of honor…. The fact that Christie's deputy chief of staff believed it was morally permissible to cause pain to innocents [by snarling traffic on the George Washington Bridge] in order to retaliate against a perceived slight, without seeking his permission, and then refused to own up to it, tells us something about the culture that Christie creates around him. She assumed the boss would be okay with what she did. And so did many other Christie advisers, including his campaign manager. And since Christie denied having anything to do with the bridge study, he apparently has fostered a culture where it's okay to lie to the boss in order to protect him.

So which do you prefer? The kind of ruthless, Nixonian maniac who's willing to screw enormous numbers of people to get revenge on someone he perceives as disloyal? Or the kind of ruthless, Nixonian maniac who builds a machine that can do that without getting him personally involved?