That Donald Trump has acted recklessly and lawlessly, without empathy, as if he lives in a world devoid of moral rules, should surprise no one. Some of us warned back in the summer of 2016 that Trump was erratic, unstable, and temperamentally unfit for office. He had what I referred to then as a “personality disorder.” I believed then and I believe now that it is the most essential thing to understand about him. Trump in power couldn’t end well.

Trump never found a way to escape the antisocial demons that haunt him. But here’s what turned a personal tragedy into a national calamity: He imprinted his moral pathologies, his will-to-power ethic, on the Republican Party. It is the most important political development of this century.

The GOP once advertised itself as standing for family values and law and order, for moral ideals and integrity in political leaders. Such claims are now risible. The Republican Party rallied around Trump and has stuck with him every step of the […]