Donald Trump returned to the White House in 2025 with a familiar weapon: social media. Once again, a handful of posts proved powerful enough to jolt Wall Street, erase trillions in market value, and reignite debates over whether presidential commentary now moves markets faster than policy itself.
Market veterans say Trump’s online activity has blurred the line between governance and market signaling. In several cases this year, a single post triggered dramatic swings across equities, tech stocks, and global indices.
Truth Social and market volatility
Early in 2025, a JPMorgan portfolio manager summed up the mood on Wall Street: markets sat “one Truth Social post away” from swinging 5% in either direction.
A JPMorgan study led by strategist Antonin Delair reviewed 126 Trump posts from late 2024 to early 2025. The analysis found that while Trump mentioned the stock market less often than during his first term, posts about tariffs remained the most powerful market movers. Nearly one-third of tariff-related posts triggered immediate and measurable market reactions.
“THIS IS A GREAT TIME TO BUY!!!” and insider trading scrutiny
The most explosive episode unfolded in April. On April 9 at 9:37 a.m. ET—minutes after US markets opened—Trump posted: “THIS IS A GREAT TIME TO BUY!!! DJT.”
At the time, investors were still digesting the fallout from “Liberation Day” on April 2, when Trump’s reciprocal tariff announcement sent the S&P 500 into a steep selloff. The market had already lost nearly $6 trillion in value over the prior week.
Roughly four hours after Trump’s post, the White House announced a sudden 90-day pause on most new reciprocal tariffs, excluding China. Markets erupted. The S&P 500 jumped 9.52%, its third-largest single-day gain since World War II, restoring about $4.3 trillion in value. The Nasdaq Composite surged 12.16%, its second-best day ever, while the Dow Jones Industrial Average climbed nearly 3,000 points.
Trump later faced intense scrutiny after shares of Trump Media & Technology Group jumped 22.67% that same day, outperforming the broader market. Democrats called for an SEC investigation, though regulators have filed no charges as of December 2025.
Trump’s China rant that wiped out $2 trillion
Another market shock arrived in October. On October 10, Trump posted a lengthy rant accusing China of acting “very hostile” over rare earth metals and export controls.
In the post, Trump warned that his administration was considering a “massive increase of tariffs on Chinese products.” Markets reacted immediately. The Nasdaq Composite fell 3.56%, its worst day since April, while the Dow dropped 879 points, marking its weakest session since May. In total, markets shed roughly $2 trillion in value in a single day.
Apple faces ‘America First’ tariff threat
Tech stocks did not escape Trump’s online pressure. In May, shares of Apple fell 3% after Trump threatened a 25% tariff unless the company shifted iPhone production to the United States.
“I expect their iPhones will be manufactured and built in the United States,” Trump wrote, warning that Apple would otherwise face steep tariffs. Bloomberg described the selloff as Apple’s eighth consecutive losing session, its longest slump since January 2022.
Trump vs. Powell rattles markets
Trump also targeted Jerome Powell, criticizing him for moving too slowly on interest rate cuts. In April, Trump publicly demanded pre-emptive rate reductions, calling Powell “Mr. Too Late.”
Markets responded nervously. The S&P 500 closed down 2.36% that day amid concerns over political pressure on the Federal Reserve. Reports later suggested Trump was considering potential replacements for Powell when his term ends in 2026, including Kevin Hassett and Kevin Warsh, further fueling uncertainty.
A presidency that trades on words
In 2025, Trump’s posts have repeatedly proven that presidential rhetoric alone can move trillions of dollars. For investors, the lesson has been stark: in a market shaped by algorithms and instant reactions, a single message from the Oval Office can matter as much as any official policy announcement.