It was there before him. It will be there after. And while gentler words from the White House and a better president may affect how much grows in it and how tall, the ugliness will always take root and always flower.

If you live in a certain category — black, brown, Jew, Muslim, gay, trans — you know this, and you experience events like those of the past week not just as chilling reflections of the political moment but as sad testaments to human nature. You register some of our gauziest bromides as well-intentioned delusions:

If only every white American knew and interacted with more black Americans. If only every straight person was aware and took stock of his or her gay relatives and friends. If only there were more mingling of Christians and Jews, of Jews and Muslims. If only the right leaders and the right thinking could reach and teach more people. If only, if only, if only.

Well, some people are beyond reaching and teaching. Some are hardened, not softened, by exposure to diversity. As best I can tell, a few of these gunmen were plenty exposed. It didn’t dim their righteousness or dissuade them of their rightness.

It’s easy to lose sight of this, to focus instead on the hearts and minds that have been changed, on the progress that can be made. I’ve been surprised and moved by the arc of L.G.B.T. Americans over my lifetime: I’m inexpressibly grateful for it. According to a recent poll, 63 percent of Americans now support same-sex marriage.

But that leaves 37 percent who don’t. And while most of them are above the age of 50, some are below 30 and — for whatever tangle of religious, cultural and psychological reasons — cannot bear the likes of me. They will be around for decades to come. So will their hate.

I note this to ward off complacency, which kicked in to some degree under our previous president. Barack Obama’s election told a narrative different from Trump’s. He symbolized the possibility of hatred’s ebb. But it was biding its time, waiting its turn. It always does.

That’s not to say that we should give in or get used to it. No, precisely because of its awesome stubbornness, we must do all we can to prevent its unleashing and weaponization. We must change overly permissive gun laws, take on a largely unregulated internet, push back at a public dialogue that abets the most destructive tribalism. We must punish acts of hate fiercely, not just to declare our values but also to make the haters think twice and to keep them in my inbox, armed with only words, and not in your child’s high school, armed with an assault rifle.