No worries.

U.S. equity markets came roaring back Monday as investors bet that a few cents more for a can of soup, or maybe a few hundred bucks more for a pickup truck, is a small price to pay for a domestic corporate environment that's turbo-charged by corporate tax cuts and insulated by a business-friendly federal regulatory regime.

Caterpillar (CAT) and Harley-Davidson (HOG) , two companies that could expect to suffer both from higher steel prices and from prospects that a trade war could hurt their overseas sales, were among the leading gainers as the Dow rose 1.4% to 24,874.76 and the S&P 500 gained 1.1% to 2,720.94. The Nasdaq Composite jumped 1% to 7,330.70.

To be sure, it's not set in stone that President Trump will order tariffs on imported steel to be raised to 25% or to 10% for aluminum, even as he seems determined to flout warnings that tariffs might complicate foreign relations and prompt retaliation. U.S. products including Levi's blue jeans, Jim Beam bourbon and Harley motorcycles are reportedly among the goods that foreign countries might seek to slap tariffs on, should the U.S. follow through.

For the moment, the White House is providing a fair amount of heat but not a lot of light. The administration is "still finalizing what the final deal will look like," press secretary Sarah Huckabee Sanders said today.

Commerce Secretary Wilbur Ross, who was on television last week waving a can of Campbell's (CPB) soup and a can of Budweiser to emphasize how little the price of aluminum affects those products, may not himself be entirely clear about what's going to transpire.

"Whatever his final decision is is what will happen," Ross said on Meet the Press over the weekend, referring to the president. After the interviewer, Chuck Todd, said perhaps that meant the tariffs aren't a "done deal," Ross said, "I didn't say that. I just said what he has said he has said. If he says something different, it'll be something different. I have no reason to think he's going to change."

Perhaps. Trump has been known to change his mind.

In the meantime, some analysts are saying that automaker profits will take a hit if the tariffs go through. Goldman Sachs analysts, including chief U.S. equity strategist David Kostin, wrote that a 25% tariff on imported steel would reduce adjusted operating income by about $1 billion, or by about 12% at Ford (F) and by about 7% at General Motors (GM) .

Over the last five trading days, Ford Motor Co. (F) stock is down 2.8%, Fiat Chrysler Automobiles N.V. (FCAU) stock has slipped 7.5% and GM has dropped about 9.1%. Investors really began selling the stocks following Trump's tariff announcement last Thursday.

On the regulatory front, things are looking a bit easier for the major U.S. banks after a top Federal Reserve official said a rule designed to keep them from making risky trades with their own capital is "not working well." The comments added to signs that firms like Action Alerts Plus holdings JPMorgan Chase & Co. (JPM) and Goldman Sachs Group Inc. (GS) could see further relief from regulations imposed in the wake of the 2008 financial crisis.

The Volcker rule -- named after former Federal Reserve Chairman Paul Volcker, who championed the measure in the wake of the crisis -- is "exceedingly complex" and should be revamped, Randal Quarles, the Fed's vice chairman for supervision, said Monday in a speech. The law is designed to keep banks from making big proprietary bets on markets that might later sour and lead to big losses.

The problem, Quarles said, was that banks have a hard time determining which trades might violate the provision.

"It should not be a guessing game or require hours of legal analysis," Quarles said. "We want banks to be able to engage in market making and provide liquidity to financial markets with less fasting and prayer about their compliance with the Volcker rule."

It's not likely that the banks will be satisfied with fasting and prayer if they should, after the repeal of the Volcker rule, have to be bailed out or borrow emergency funds from the Fed in some future financial crisis.

Until then, the Trump trade rolls on.

Anders Keitz and Brad Keoun contributed reporting for this article. Contact the author: john.pickering@thestreet.com.

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