There are problems with impeaching Donald Trump. A big one is the holy terror waiting in the wings.

That would be Mike Pence, who mirrors the boss more than you realize. He’s also self-infatuated. Also a bigot. Also a liar. Also cruel.

To that brimming potpourri he adds two ingredients that Trump doesn’t genuinely possess: the conviction that he’s on a mission from God and a determination to mold the entire nation in the shape of his own faith, a regressive, repressive version of Christianity. Trade Trump for Pence and you go from kleptocracy to theocracy.

That’s the takeaway from a forthcoming book by the journalists Michael D’Antonio, who previously wrote “The Truth About Trump,” and Peter Eisner. It’s titled “The Shadow President: The Truth About Mike Pence,” it will be published on Aug. 28 and it’s the most thorough examination of the vice president’s background to date.

I got an advance look at it, along with a first interview about it with D’Antonio, and while it has a mostly measured tone, it presents an entirely damning portrait of Pence. You’ve seen his colors before, but not so vividly and in this detail.