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The writer is the senior White House counsellor for trade and manufacturing

Every so often, what looks like a defeat proves to be a strategic win. The Supreme Court’s ruling on US President Donald Trump’s tariffs is one of those moments. 

On its face, the ruling looks like a knockout punch. In a 6-3 decision, the court held that the International Emergency Economic Powers Act’s authorisation to “regulate importation” does not include the power to impose tariffs. Because tariffs raise revenue, the majority concluded, they are in effect taxes — and taxes require explicit congressional approval. 

But look carefully at what the court actually did. It ruled that the IEEPA does not authorise tariffs. That’s all. 

The court did not declare tariffs unconstitutional. It did not strike down section 232 of the Trade Expansion Act. It did not invalidate section 301 of the Trade Act. It did not question the use of sections 122, 201 or 338. It did not revive the “nondelegation” doctrine. And only three justices relied on the “major-questions” doctrine, meaning the court created no sweeping precedent limiting presidential trade authority. 

In fact, even as the court struck down the IEEPA tariffs, it acknowledged that the president retains broad and powerful authority under numerous other statutes to impose tariffs. 

Justice Brett Kavanaugh’s dissent offered a rigorous and historically grounded defence of presidential tariff power. He emphasised the historical understanding that tariffs are a traditional form of regulating imports. He also catalogued the full range of statutory authorities that remain fully intact. 

President Trump is already relying on many of them: section 232 of the Trade Expansion Act of 1962 to impose national-security tariffs on products such as steel and aluminium, and — potentially — on critical minerals; section 301 of the Trade Act of 1974 to impose country-specific tariffs in response to unfair trade practices — as with China; section 201 safeguard measures, used in his first term to impose tariffs on solar panels and washing machines, with the solar protections still in place; and section 122, just invoked to implement a temporary global surcharge. 

Kavanaugh went further, underscoring that additional tools remain available — including section 338 of the Tariff Act of 1930, which authorises retaliation against discriminatory foreign trade practices. In short, the court closed one door while leaving an entire corridor of tariff authority wide open. 

Moreover, by narrowing the legal dispute in this case to the IEEPA alone, the court clarified the legal landscape. The authority under those other statutes is not in doubt. It is written clearly into law. That clarity will significantly strengthen the president’s tariff hand. 

Trump has noted that he has been “very modest” in his initial ask of trading partners. That restraint is over. Any country that believes the court’s ruling strengthens its hand — or allows it to walk away from the bargaining table — is misreading the moment. 

What makes the majority’s decision so striking is its internal contradiction. As Trump noted, a president may impose a “Foreign Country destroying embargo”, wiping out trade entirely, but he cannot impose even one dollar in tariffs because it collects revenue. Total prohibition is fine. A calibrated fee is not. As Kavanaugh explained in dissent, that distinction defies history and common sense: tariffs have always been understood as a core means of regulating imports. They influence price, volume and competitiveness. They serve as leverage in negotiations. They are tools of economic statecraft. As he rightly noted, it makes no sense to allow the more extreme power to ban trade while forbidding the lesser power to condition it. 

The solicitor-general correctly argued that a tariff is not a domestic tax. Early Congresses relied on this distinction. Courts acknowledged it. In the broader trajectory of US trade policy, Friday’s ruling will register as a technical correction, not a strategic reversal. 

As Trump noted, countries that have been “ripping us off for years” may be “ecstatic, and dancing in the streets — But they won’t be dancing for long.” The tools remain, and the statutory footing beneath them is now clearer. 

A 15 per cent global surcharge is already in place under section 122 authority. Section 232 continues to safeguard industries vital to national security. Section 301 investigations are advancing country by country and practice by practice. Other tariff authorities identified in the court’s own ruling remain fully available. 

The architecture of American trade enforcement has not weakened. It has recalibrated. America will trade and negotiate — but it will not be exploited.