“How dark is your mood?” Fox News host Chris Wallace asked President Trump on “Fox News Sunday,” citing “a number of stories out there that you’re angry” about the midterms, Trump’s recent Paris trip and, of course, the media. The president’s brave face lasted three whole words: “It’s very light,” he said; then he called the reports “disgusting fake news.” So much for a “light mood.” Much of the interview was the usual Trump testiness and ineptitude, but there was one revealing moment at the very end that tells us a lot about 2020.

To end the sitdown, Wallace told Trump he had been in Missouri “talking to a lot of loyal Republicans. They love what you’ve done to the economy. They love the fact that you have basically put ISIS out of business. The one thing they say is, why do you have to be so divisive? Why don’t you do more to bring the country together?”

Trump replied, “I think that if I was very different, I wouldn’t have gotten what we had to get. We got the biggest tax cuts in history, we got [oil development in the Arctic National Wildlife Refuge] approved, we have — we got rid of the individual mandate, which was the most unpopular thing you can imagine, health care — I got rid of it. … I think if I was a, you know, more modified, more moderate in that sense, I don’t think I would have done half of the things that I was able to get completed.”

Last week, The Post reported that recent election results set off “five days of fury” from Trump. The quote above suggests that even after brooding over the midterm shellacking, Trump won’t learn from it and change his rhetoric. There may be some gestures at moderation — as when last week he offered to help Rep. Nancy Pelosi (D-Calif.) secure votes to be speaker of the House. But Democrats can rest easy knowing that in 2020 Trump will still be repeating the mistakes that helped them in 2018.

But this isn’t a surprise, some readers may say, because Trump doesn’t change. Yet there is actually plenty of precedent for major course corrections from Trump. The man who once built his own buildings with largely domestic investors now makes most of his money by leasing his name to other people’s properties and/or using overseas investment. The real estate businessman moved to headlining a television franchise, which switched from real contestants to celebrities halfway through its run. He’s tried selling wine, steak, deodorant and a dozen other products. He has ventured into casinos, airlines and even a football team, with the only commonality being that they all failed. Even in politics, Trump for years flirted with third-party runs on the Reform Party ticket long before coming home to the GOP.

Sure, many of these changes resulted from external pressure — lack of investors, for example. But there’s little distance between banks not buying what you’re selling and voters not backing what you’re pushing. And as much as Trump likes to pretend he’s immovable, he has made deals with reality before. But this time, he has opted to reject reality instead. Which, for politicians, usually ends poorly.

Read more:

Greg Sargent: Why did Trump’s lies fail so badly? Important new data provides a clue.

The Post’s View: Trump is defending Mohammed bin Salman’s lies. Congress must insist on the truth.

Joe Scarborough: Trump lost. And it wasn’t even close.

Karen Tumulty: Trump is right: Nancy Pelosi should be the next speaker