It wasn’t, and this week President Trump said he would use it for the first time in its near-century existence to hit Canada with 50% tariffs.

When the Supreme Court struck down Trump’s main tariff weapon in February, the president’s trade war seemed destined to enter a less capricious and more constrained phase.

To Trump, though, court rulings are road maps, not roadblocks. February’s court ruling simply rerouted him to tools the court hadn’t explicitly prohibited. And fortunately for Trump, Congress has over the years scattered many such tools through the law books, many largely forgotten or unused. 

In the past two weeks Trump has announced tariffs of 25% on Brazil, 50% on Canada and up to 200% on generic drugs, and on Thursday, tariffs of 10% to 12.5% across as many as 60 trading partners. The upshot: Trump can wage a trade war that is as sweeping and capricious as before the Supreme Court ruled.

Tariffs are central to Trump’s vision of presidential power: a catalyst for national rejuvenation, a source of revenue and an all-purpose crowbar to force allies and adversaries alike to do what he wants, from lowering their own trade barriers to surrendering territory.

This vision is at odds with the Constitution, which gives Congress authority over tariffs and taxes, except when delegated to the president for specific reasons. It also breaks with the bipartisan consensus in Congress that trade policy should enhance strategic bonds with allies and neighbors. 

Early on, Trump thought he had just the device to sidestep both constraints: the International Emergency Economic Powers Act of 1977. Originally intended to sanction rogue nations like Iran, he claimed it let him tariff anyone for any reason indefinitely. He used it for his first big tariffs, supposedly over fentanyl, against Canada, Mexico and China, and then in April last year against almost everyone.

In February, though, the Supreme Court said the law didn’t explicitly authorize tariffs, and that Congress wouldn’t delegate so much of its power to the president without expressly saying so.

Trump immediately sought to accomplish the same thing using different laws: Section 122 to impose a temporary, 10% universal tariff, Section 232 and Section 301 to set industry- and country-specific tariffs. 

Trump had boasted his Ieepa tariffs would raise enough money to replace the income tax. Though an exaggeration, it hurt his case at the Supreme Court since taxes are clearly Congress’s purview.

Yet with these new tariffs, Evercore ISI, an investment bank, estimates Trump will raise a hefty $240 billion to $260 billion a year, just 20% less than before the Supreme Court ruling and still triple the pre-Trump level.

Trump likes to impose and repeal tariffs without notice, for maximum effect. The problem with 232 and 301 is that they require lengthy periods of investigation and comment. Not 338, though. 

“This is possibly the new Ieepa,” said Sarah Bianchi, a former trade official under President Joe Biden who is now a policy analyst with Evercore ISI. “If he’s able to use this tariff for leverage, I don’t know why he wouldn’t keep trying. As to which one is next, the European Union would be on your list.”

Veroneau, a trade official under President George W. Bush and now senior counsel at Covington, said Section 338 was aimed at countries that discriminated against the U.S. relative to other partners. Its goal was “most-favored nation” status, that is equal treatment of all trading partners, which the U.S. was eventually able to achieve through negotiation.

Trump’s use of 338 is “ironic if not perverse,” Veroneau said, because under the North American Free Trade Agreement, now the U.S.-Mexico-Canada Agreement, Canada gives the U.S. better access than it does to most other countries. It was Trump who then overrode those pacts to hit Canada with duties on steel, aluminum, autos and other goods. Canada retaliated, and Trump is now punishing Canada for retaliating. In effect, he is laying down the principle that discrimination is acceptable as long as it’s the U.S. doing the discriminating. (Under USMCA, Canada does restrict U.S. dairy imports. Trump claims the EU gets better terms.)

Trump regularly deviates from the original intent of the trade laws he deploys. Section 122 was aimed at balance-of-payments problems, a feature of a fixed exchange-rate system that ended over 50 years ago. Section 232 is meant to protect industries vital to national security, which Trump now defines to include everything from lumber to generic drugs.

Section 301 is aimed at unfair practices that discriminate against U.S. products, such as China’s industrial subsidies. It will now be used to penalize other countries’ failure to police their own imports for forced labor. That these are pretexts haven’t, to date, mattered to courts who have declined to block any.

Many in Congress regret ceding so much power to the president on tariffs. “It’s well past time to put Congress back in the driver’s seat on trade,” Sen. Ron Wyden (D., Ore.) said at a Senate Finance Committee hearing Wednesday.

And yet Congress may be about to cede to Trump even more power. Just before he died, Sen. Lindsey Graham (R., S.C.) had finally persuaded Trump to back a bill imposing steep tariffs on Russia for invading Ukraine, and the largest buyers of its oil and gas. At Trump’s behest the bill was weakened, allowing Trump to issue waivers. The bill is gaining support in the Senate, while its fate in the House is unclear.

The bill would enable Trump to use tariffs instead of sanctions for geopolitical goals, something the Supreme Court said he couldn’t do under Ieepa. But trade and sanctions expert Peter Harrell said as written, the bill would perversely let Trump waive tariffs on Russia, then tariff the EU for refusing to back his war with Iran. Harrell, who was an adviser to Biden, noted Trump already has the authority to sanction Russia but has barely used it.

“It makes me a little suspicious,” said Harrell. “If he does not seem interested in putting pressure on Russia, but does seem interested in this bill, what would his interest be? The tariffs.”