Since the State of the Union address now feels as historically distant as the Second Punic War (the one with Hannibal and the elephants), it is a risky proposition to claim that any Donald Trump speech will be long remembered.

But Trump’s Monday tax-cut speech was among the most emblematic — and inadvertently memorable — of his presidency. Gone was Teleprompter Trump, an alien figure who, if you squint hard enough, might seem vaguely like a normal president.

In his place was Tantrum Trump, a divisive figure who lashes out at his enemies with a level of vitriol unseen in American politics since Roy Cohn (a Trump mentor) was advising Joe McCarthy in the 1950s.

Reliving the State of the Union (which Trump alone still remembers), the president referred to the deliberately silent Democrats: “They were like death. And un-American. Un-American. Somebody said treasonous — I mean — yeah, I guess, why not? Can we call it treason? Why not, I mean, they certainly didn’t seem to love our country very much.”

Treason is an explosive word normally associated with Benedict Arnold and wackadoodle conspiracy theories. During the 1960s, the John Birch Society distributed a book entitled “None Dare Call It Treason” about how elite groups like the Council on Foreign Relations furthered the international Communist Conspiracy.

But here is the president of the United States using the word to describe Democrats who — horrors! — failed to clap at the State of the Union.

Flake Slams Trump For ‘Treason’ Comments

Cleanup duty

White House press secretary Sarah Sanders, performing her usual post-circus cleanup role, claimed Tuesday that Trump was “clearly joking.” And her deputy, Hogan Gidley, chimed in to suggest that the extended riff on treason was “tongue-in-cheek.”

These defenses from paid Trump staffers should go into the file marked, “They would say that, wouldn’t they?”

If Trump had suggested that the Democrats should be “taken outside and shot,” some sycophant in the White House would have instructed the news media to appreciate the president’s “great sense of humor.”

And treason should be no laughing matter, since it is one of the rare federal crimes that carries the death penalty.

Why does Trump say things like this?

The most charitable theory is that the president has no idea what the word “treason” means. After all, no one (not even Sean Spicer) has ever suggested that Trump rivals Winston Churchill in his mastery of the English language.

Another possibility is that Trump in his Fortress of Ego is so convinced that he rivals Abraham Lincoln’s greatness that he cannot conceive of any red-blooded American not bowing down in awe of his epic accomplishments. In this case, not applauding Trump is akin to “giving aid and comfort” to America’s enemies.

The third — and most alarming — interpretation is that Trump shares the views of his role model, Vladimir Putin, about even the mildest forms of dissent. And it is hard to be more Gandhi-esque than not clapping. Remember that on State of the Union night, no Democrat yelled, “You lie,” at the president.

Spoiling for a fight

In political terms, the president’s treason-season rhetoric illustrates that there is no occasion — no matter how bland it looks on the White House schedule — that Trump cannot mar with his vitriolic outbursts.

When the president hits the campaign trail this fall, Republicans should immediately go into a protective crouch in the knowledge that Trump will say something that every GOP candidate will have to spend the next four days trying to explain away.

Until Monday, it had been widely assumed that the cable networks would never dare break away from a Trump speech even if an alien spaceship collided with the Eiffel Tower.

But all it took was a four-digit drop in the Dow Jones industrial average for the cable networks to switch to breaking-news market updates. Had Trump known that his favorite TV network had interrupted his speech, the wounded president might have channeled his inner Julius Caesar to shout, “Et tu, Fox News?”

With the markets bouncing back on Tuesday, optimists will view Monday’s death-defying descent as an odd blip soon to be forgotten amid the prosperity gospel. But at a minimum it should serve as a warning about the risks of a chest-thumping president bragging about how he’s “always been great with money.”

In terms of the narrow question of who will be House speaker in 2019, the biggest news of the month was probably the Supreme Court’s refusal to take up the Pennsylvania gerrymandering case. That means that the Democrats are almost certain to pick up a few Pennsylvania House seats under a new 2018 map to be drawn under state court order.

All the news Monday offered a crash course in the folly of trying to predict the 2018 elections nine months in advance.

Yes, you can create ambitious polling models that would have made George Gallup drool with envy. You can brandish off-year congressional statistics dating back to 1798. But you cannot fully anticipate the electoral environment in November.

Here are some of the questions that are unknowable at the moment: Where will the stock market sit? Will economy seem as healthy as in February? Will Trump have blundered into a war with North Korea? What is the status of the Robert Mueller investigation? What self-inflicted controversy is swirling around Trump? Have the primaries produced unelectable candidates in either party? Which party holds the financial and enthusiasm edge?

Trump declared Monday, “I think we’re going to do well in ’18.” Unlike many Trump statements, this one will be tested by reality. And if he’s wrong, it will be hard to denounce a Democratic House as “fake news.”