Wall Street is alarmed at the prospect of President Elizabeth Warren. As the Massachusetts senator rises in the polls, famed investors such as Leon Cooperman and Paul Tudor Jones have been warning that stocks would fall 25% or more if she becomes the Democratic nominee and wins the general election a year from now.

Investors should chill out. Warren does have radical plans for euthanizing the private health insurance industry, marginalizing fossil fuels, breaking up Big Tech and shackling the financial industry. She’d sharply raise taxes on businesses and the wealthy to finance as much as $4.2 trillion per year in new spending on social programs and enriched benefits.

But much of Warren’s agenda would require Congressional legislation, and even a fully Democratic Congress would balk at the scope, cost and disruption inherent in some of Warren’s most grandiose plans. Warren could try to impose other policies through regulatory channels and executive power, but like President Trump, she’d encounter lawsuits and other forms of pushback constraining her ability to enact radical change.

Trump’s election in 2016 illustrates the folly of predicting the stock market’s reaction to future presidential policies. During the 2016 campaign, several respected forecasting firms predicted a recession and bear market in stocks if Trump won the election. Trump won, but there’s been no recession, and stocks have risen 44% since Election Day in 2016.

Campaign promises that don’t come to pass

But those predictions were based on Trump doing everything he said he would during the campaign. He hasn’t. Trump said he would apply a 45% tariff on all Chinese imports and a 35% tariff on all non-petroleum imports from Mexico. In reality, he has imposed much smaller tariffs on some Chinese imports and no new tariffs on Mexican imports. Trump also said he would deport 11.3 million undocumented immigrants who make up 5% of the U.S. labor force. He hasn’t done that, either. Nor has he repealed the Affordable Care Act, as promised.

What Trump has done is cut taxes, which if anything is a net positive for the stock market. So with the exception of the China tariffs, Trump has abandoned campaign promises that would hurt stocks and pursued those that help. Those gloomy forecasts weren’t necessarily wrong. Instead, they analyzed circumstances that haven’t come to pass.

It’s probably the same for predictions based on Elizabeth Warren’s policies. It probably would convulse markets if Warren massively raised corporate taxation, eliminated the health insurance and fracking industries, shackled the financial sector and waged war on tech firms. Profits would drop, and stock prices with them. But many Democrats in Congress are friendlier toward business than Warren, and they wouldn’t go along with all this—just as some Republicans have broken with Trump on trade, foreign policy and other issues.

As president, Warren wouldn’t be able to dismiss worries about the stock market as blithely as she can as a candidate. More than half of all Americans own stocks in some form, mostly in retirement plans. No president can trigger a stock market plunge and survive politically, as nest eggs shrivel and retirement fears mount.

As a candidate, Warren can pretend only evil billionaires benefit from a buoyant stock market. But if she’s ever president, Warren will have to face the reality of a stock market that punishes bad policies damaging to the economy. Bear markets hammer consumer confidence and sometimes generate recessions. Because of that, they can also shorten political careers.

Rick Newman is the author of four books, including “Rebounders: How Winners Pivot from Setback to Success.” Follow him on Twitter: @rickjnewman. Confidential tip line: [email protected]. Encrypted communication available. Click here to get Rick’s stories by email.

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