At the level of raw politics, this deal has worked. A president who panders to the religious right may end up being more reliable than a leader who is actually a religious conservative and thinks for himself or herself. Pandering is utterly predictable. Conscience makes distinctions.

But there is a downside to the deal. This particular demagogue requires not just consent but approval. And not just approval but obeisance. So religious conservatives end up blessing what Pete Buttigieg, a 2020 Democratic presidential hopeful and the mayor of South Bend, Ind., memorably called “the porn-star presidency.” Deficit hawks vote for massive increases in debt. Economic conservatives accommodate the instincts of an economically illiterate leader. Military hawks endorse a foreign policy that resembles President Barack Obama’s, except with more praise of dictators and less backbone.

To ensure the political triumph of their views, these partisans must publicly dilute and discredit those views. Trump offers true believers an uncomfortable arrangement: What you would save you must first defile.