Will it weaken us to remember The Alamo — that is, the reality of what was at stake in 1836?

You would think that humans, as the creatures at the very top of the phylogenetic scale in the known world, would be quite good at recognizing what’s true, and would welcome knowing it. Delusion can be dangerous, after all — do not ignore chest pains or bald tires! — and we’re told by a no less authoritative source than the Bible that the truth shall set us free. We want to know and to accept what’s true, right?

Actually, we’d rather not. And while there are plenty of examples of truth aversion in public life these days, the political starts with the personal. Maybe we’re uncomfortable with hard truths about America because we haven’t learned to welcome them about ourselves. Yet being true to “thine own self,” Shakespeare elegantly suggested, is our most essential ability.

So why are so many of us finding it so hard these days to agree on what is simply true? Look, we all have both strengths and…