It’s important to realize that the zombification of the G.O.P. isn’t a recent phenomenon, something that happened only with Trump’s election. On the contrary, zombies have been eating Republican brains for decades. Voodoo economics had completely taken over the party by the early 2000s, when then-House majority leader Tom DeLay declared, “Nothing is more important in the face of war than cutting taxes.” Climate deniers have ruled since at least 2009, when only eight House Republicans supported a bill to limit greenhouse gas emissions.

What recent events make clear, however, is that zombie ideas haven’t eaten just Republicans’ brains. They have also eaten the party’s soul.

Think about what is now required for a Republican politician to be considered a party member in good standing. He or she must pledge allegiance to policy doctrines that are demonstrably false; he or she must, in effect, reject the very idea of paying attention to evidence.

It takes a certain kind of person to play that kind of game — namely, a cynical careerist. There used to be Republican politicians who were more than that, but they were mainly holdovers from an earlier era, and at this point have all left the scene, one way or another. John McCain may well have been the last of his kind.

What’s left now is a party that, as far as I can tell, contains no politicians of principle; anyone who does have principles has been driven out.

Now, the news media, with its constant urge to seem “balanced,” has a hard time coping with this reality; it’s always looking for ways to portray at least some Republicans as admirable figures. This has made it easy prey for charlatans like Paul Ryan, who pretended to be serious about his fiscal principles. But he was always an obvious flimflam man.

Anyway, a result of decades of zombification is a Republican caucus that consists entirely of soulless opportunists (and no, the fact that some of them like to quote Scripture doesn’t change that fact).

I guess you might have hoped that there would be some limits to what these apparatchiks would accept, that even they would draw the line at gross abuses of power and collusion with foreign autocrats. What we’ve learned, however — and perhaps more important, what Trump has learned — is that there is no line. If Trump wants to dismantle democracy and rule of law (which he does), his party will stand with him all the way.

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