The phrase, a play on the popular Mexican dish, was Armstrong’s way of describing Donald Trump’s now-predictable pattern: threatening to impose steep tariffs, only to back down shortly after. “Markets have learned that the U.S. administration doesn’t tolerate economic pain well,” Armstrong wrote. “It retreats once tariffs start to hurt. That’s the TACO theory—Trump Always Chickens Out.”

And just like that, TACO was born.

It didn’t take long for the term to go viral. Financial feeds on X (formerly Twitter) were soon flooded with memes, hashtags, and mock analyses. Investors began jokingly referring to “Taco Trades”—buying stocks low when Trump rattled markets with tariff threats, and cashing in when he predictably reversed course. The existence of a taco emoji only helped the meme take off.

Then came Wednesday.

During a press briefing in the Oval Office, Trump was asked about TACO. He hadn’t heard of it—and he did not like it.

“I chicken out? Never heard that before,” Trump barked. “That’s disgusting. Don’t ever say that again.”

He was reportedly furious afterward, scolding his aides for not alerting him to the joke circulating at his expense. According to White House sources, the president’s anger stemmed not only from the ridicule itself, but from what it attacked: his self-styled image as a tough-as-nails negotiator and dealmaker, the very persona he built in The Art of the Deal.

Insiders added that Trump felt the nickname undermined what he views as a strategic trade tactic. He even tried to clarify during the same press event: that he often sets intentionally “ridiculously high” tariff rates to pressure other countries into making concessions—then backs off if they comply.

Still, the damage was done.

“The joke clearly got under his skin,” one White House source told CNN. “It shows a fundamental misunderstanding of how he uses threats as leverage. And frankly, Trump doesn’t tolerate being seen as weak—so the idea that people think he ‘chickens out’ stings hard.”

Whatever Trump’s intentions, Wall Street has largely stopped taking his tariff threats at face value. Last Tuesday, markets surged after Trump once again postponed imposing 50% tariffs on the EU—just days after threatening them. A similar rally followed Wednesday, after a federal court ruled many of Trump’s tariffs illegal. Though the administration immediately appealed and secured a temporary freeze on the ruling pending a June 9 hearing, the pattern repeated itself yet again.

As for Robert Armstrong, he was stunned by the wildfire spread of his TACO theory.

“The mystery of social and traditional media remains utterly beyond me,” he said on the Financial Times’ popular podcast Unhedged. Still, he offered a tongue-in-cheek warning:

“What I really hope doesn’t happen is that Trump stops chickening out because of what I wrote. Let’s be clear: his retreats are the right thing to do. They’re worth celebrating. Three cheers for chickening out of bad policy.”

In the end, what began as a clever acronym has become a symbolic critique of Trump’s trade strategy—and a rare moment where a financial columnist found himself under the President’s skin, simply by calling his bluff.