Memories being short, who remembers a distant age when stock markets would soar like rockets, and then plummet like the Wall Street brokers of Great Depression urban myth who leapt from 27th floor windows?

In a time of market serenity, as expertly overseen by President Donald J Trump, you need look elsewhere for a reminder that shares can fall as sharply as they can rise. No one is more useful tutorial here than Trump’s erstwhile policy guru, Steve Bannon.

A few months ago, shares in Bannon, the dishevelled victim of a chronic skin condition too easily mistaken for Boozer’s Blotch by those with no dermatological training, were at dizzying levels.

From his standing position behind the Resolute Desk in the Oval Office, he bestrode Washington like a white supremacist colossus. Widely credited with having rescued a doomed campaign by liberating Trump to be Trump, he held the title of White House chief strategist.

For a while, he was seen as the de facto President, before the magazine covers and Saturday Night Live caricatures as Darth Vader displeased the actual one whose brittle narcissism is poorly equipped for the sharing of spotlights.

Bill Murray unveiled as Steve Bannon on Saturday Night Live

Even after his firing, he was a human bitcoin – dramatically reduced in value, but still worth a fair chunk in the guise of maverick guardian of alt-right values. In that highly volatile market, he hoped to use his Breitbart bully pulpit to recover (he was contemplating a presidential run in 2020), by completing the Republican transformation from the gerrymandering machine of Dick Cheney and Karl Rove into an endless, riotous celebration of the absolute worst this species has to offer.

Then came the “Judge” Doug Jones fiasco in Alabama, where there weren’t quite enough Confederate flag-wavers and Lynyrd Skynyrd megafans to do Bannon’s bidding by sending a good ol’ boy with a keen historic interest in li’l girls to the Senate. His share price crashed again.

And just look at him now, the megaphonic zealot of American exceptionalism, risking a contempt charge by ignoring a subpoena to testify before a Congressional committee about Russian collusion.

The reticence is charmingly belated. When Michael Wolff asked him about Trump campaign connections to Russians while researching Fire and Fury, Bannon was not inclined to silence. He sang like a canary, and no average canary. He sang like the canary known to his cagemates as “Squealer” after being pumped with whatever truth serum the Avian CIA was trialling last year.

“The three senior guys in the campaign thought it was a good idea to meet with a foreign government inside Trump Tower …” Bannon told Wolff of Donald Jr, Jared Kushner and Paul Manafort, “with no lawyers”.

“Even if you thought that this was not treasonous, or unpatriotic, or bad shit, and I happen to think it’s all of that, you should have called the FBI immediately.” He conservatively estimated the chances of Donald Sr not being involved in that meeting at “zero”.

Ah, treason, treason … what an amazing journey the word’s been on since the mores of reality TV and the leadership of the free world met in a Venn diagram intersect. Once, it was a pretty clear legal concept, covering covert assistance with a foreign power at the expense of one’s own. Selling state secrets, plotting to remove a head of state, colluding with a hostile government’s agents to rig an election, that kind of stuff.

Then the frothing far right hijacked it – just as they moulded “freedom” into a synonym for “borderline fascist” – and redefined it as: “any divergence from anything we claim to believe”.

Ten years ago, the Tea Party widened its scope to include any failure by any Republican politician to oppose anything Barack Obama attempted to do.

Now Donald Trump puts more flesh on the etymological bone. “Somebody said, ‘treasonous’,” he recalled about Democrats who didn’t applaud his State of the Union address with warranted enthusiasm. “I mean, yeah, I guess why not? Can we call that treason? Why not?”

Why not indeed? Why not call it “aardvark”, come to that, or “dewflap”, or “Oswestry”? In a neo-Orwellian bizarro world where objective fact can be manufactured and retroactively superimposed on pre-existing fact, words and their definitions are matters of personal choice. If you don’t like it, tough. That’s the way the covfefe crumbles.

Sadly, Bannon is less adept at this than his former boss. Where Trump would have claimed he used “treasonous” in its traditional meaning of “so patriotic; just tremendously loyal”, Bannon hinted that he made the allegation in confusion caused by his military background.

In a futile bid to dissuade Trump from short-selling what was left of his reputation, he said that “treasonous” referred solely to the indicted Manafort, and not to Kushner or, God forbid, the eighth-witted Don Jr.

“My comments about the meeting with Russian nationals came from my life experiences as a naval officer stationed aboard a destroyer,” Bannon went on, “whose main mission was to hunt Soviet submarines … when our focus was the defeat of ‘the evil empire’.”