Donald Trump’s election helped turbocharge an already surging bull market in the U.S., sending stocks and cryptocurrencies to record highs.

Now, some on Wall Street are beginning to sound the alarm that the fast times can’t last.

JPMorgan Chase CEO Jamie Dimon and others have warned that investors are plowing cash into stocks with inflated prices. Hedge fund giant Elliott Management said the blistering rise in crypto over the last year, with bitcoin up 89 percent, is the stuff of bubbles. So-called memestocks — companies like GameStop, whose shares tend to be driven by investor hype — have returned. And on top of that, economists say Trump’s plans for tariffs and an immigration crackdown — along with the dizzying pace of his policy moves — could roil the markets by stoking inflation and fueling uncertainty.

“For good or bad, depending on your politics, we’re back to the chaos presidency,” said Jim Chanos, a hedge fund manager who famously bet against Enron and other failing companies. “Whatever you might think about the Biden administration, if you were a market participant, you generally didn’t need to check your Twitter feed the first thing in the morning when you woke up just to see what was said. But we’re back to that, and with that, comes probably more volatility.”

It isn’t just Trump, of course. The markets are coming off back-to-back banner years fed by a mix of pandemic stimulus money, wild optimism about artificial intelligence, and a supersized interest rate cut by the Federal Reserve last year. But the brewing anxiety over an overvalued market now portends potential problems for the White House.

Trump — who is fond of touting market highs as indications of his success as America’s chief executive — is fixated on lifting up businesses and consumers. A stock market slide could undercut his reputation as a pro-growth president and scramble his administration’s economic plans if it’s forced to deal with the fallout.

“Everyone who puts on the nightly news or even watches Twitter knows what the stock market does every day,” said Ed Hill, a veteran financial industry lobbyist. “It’s become a preferred measure of the economy, even though we all know it doesn’t really reflect the economy. People are going to be very sensitive. This administration particularly is going to be very sensitive to markets.”

To be sure, naysayers are nothing new on Wall Street or in crypto, and Trump’s allies argue that the president’s plans will boost the markets over time.

Hal Lambert, a Republican donor and founder of investment management firm Point Bridge Capital, said the combination of Elon Musk’s cost-cutting campaign, the expected extension of the 2017 tax cuts, and lower oil prices represent major economic windfalls to come. And in the meantime, he said, U.S. stock investors aren’t going anywhere.

“People aren’t going to sit around and hold money markets, and they’re not going to sit around and buy three [or] four percent Treasuries,” Lambert said. “They’re going to keep investing in the equity markets.”

Indeed, investors aren’t slowing down much. The benchmark index for U.S. stocks, the S&P 500, closed at a new all-time high Wednesday. And crypto has continued to surge, with bitcoin — the world’s most valuable crypto token — remaining at sky-high valuations after breaking through $100,000 earlier this year.

Most Wall Street banks and research shops still believe investors are in for a generally positive 2025, as do everyday buyers themselves. More than half of consumers are expecting stocks to increase over the course of 2025, according to the Conference Board.

The Nasdaq Composite fell more than 1% on Monday, with big technology stocks creating the biggest drag as investors worried about demand for technology supporting artificial intelligence while they waited for results from market heavyweight Nvidia. The S&P 500 closed slightly lower, marking its third straight day of declines, while the Dow managed to eke out a tiny gain. It was also Nasdaq’s third consecutive loss and its fourth daily drop of more than 1% so far in February. Investors were concerned about future demand for Nvidia’s (NVDA.O), opens new tab pricey AI chips as they awaited its quarterly results on Wednesday. Worries about hefty spending on the technology have mounted since low-cost AI models from China’s DeepSeek rattled the industry in January. Adding to uncertainty, a TD Cowen analyst note published late on Friday reported that Microsoft Corp (MSFT.O), opens new tab has scrapped leases for sizeable data center capacity in the U.S., suggesting a potential oversupply of AI infrastructure. Microsoft said its plan to invest over $80 billion in AI and cloud capacity this fiscal year was intact but that it “may strategically pace or adjust” infrastructure in some areas. “Markets are already jittery and looking for a reason to take profits,” said Gene Goldman, chief investment officer at Cetera Investment Management, noting that any question about AI is seen as a reason to take profits since the technology has driven market growth for the last few years. Along with worries about tariffs and inflation, investors are getting more anxious about economic growth after last week’s batch of weak economic data and a disappointing forecast from Walmart (WMT.N), opens new tab. “Volatility is being driven by market uncertainty about whether we’re facing a growth scare or an inflation scare,” said Goldman. The Dow Jones Industrial Average (.DJI), opens new tab rose 33.19 points, or 0.08%, to 43,461.21, the S&P 500 (.SPX), opens new tab lost 29.88 points, or 0.50%, to 5,983.25 and the Nasdaq (.IXIC), opens new tab lost 237.08 points, or 1.21%, to 19,286.93. The more defensive healthcare index (.SPXHC), opens new tab led percentage gains, closing up 0.75% while technology (.SPLRCT), opens new tab was the biggest laggard, ending down 1.43%. Nvidia was the S&P 500’s biggest index point drag, ending the session down 3.1%, and it was followed by chip maker Broadcom Inc (AVGO.O), opens new tab, down 4.9%, Amazon.com (AMZN.O), opens new tab, down 1.8%. Microsoft shares ended down 1%. The tech sector’s biggest percentage decliner with, a 10.5% drop, was another popular AI stock, Palantir Technologies (PLTR.O), opens new tab. “The dominance of the AI tech trade has run its course, not that these companies aren’t great stocks. We’re headed for a major digestion phase,” said Peter Boockvar, CIO at Bleakley Financial Group. On the data front, the Personal Consumption Expenditure index – the Federal Reserve’s preferred inflation gauge – is expected on Friday and could help markets gauge the timing of the central bank’s first rate cut this year. Interest rate futures indicate trader expectations that the Fed will leave borrowing costs unchanged until June, according to CME Group’s FedWatch, opens new tab tool. In individual stocks, Apple (AAPL.O), opens new tab finished up 0.7% after the iPhone maker unveiled plans to spend $500 billion in U.S. investments in the next four years, including setting up a factory in Texas for AI servers. Berkshire Hathaway (BRKa.N), opens new tab, shares hit record highs in early trading, after Warren Buffett’s conglomerate reported a record annual profit and its class B shares ended up more than 4%. Nike (NKE.N), opens new tab finished up 4.9% after Jefferies raised its rating to “buy” from “hold”. Declining issues outnumbered advancers by a 1.25-to-1 ratio on the NYSE where there were 90 new highs and 134 new lows. On the Nasdaq, 1,518 stocks rose and 2,888 fell as declining issues outnumbered advancers by a 1.9-to-1 ratio. The S&P 500 posted 28 new 52-week highs and 8 new lows while the Nasdaq recorded 40 new highs and 232 new lows. On U.S. exchanges about 15.32 billion shares changed hands compared with the 15.34 billion average for the last 20 sessions.