The US Supreme Court’s decision to strike down the core of Donald Trump’s broad tariff regime has altered the legal basis of Washington’s trade policy, but it is unlikely to trigger a rapid collapse of trade understandings already signed with US partners.
The immediate reason is straightforward: the ruling narrowed one presidential tool, but it did not eliminate the wider tariff arsenal available to a Trump administration. In its February 2026 judgment, the Court held that the International Emergency Economic Powers Act (IEEPA) did not authorise the sweeping tariffs imposed under Trump’s “reciprocal” approach. The ruling therefore removed a central pillar of the 2025 tariff programme.
However, within hours, Trump signalled a shift to other legal routes, including Section 122 of the Trade Act of 1974, which allows temporary import surcharges for up to 150 days, and the continued use of sectoral mechanisms such as Sections 232 and 301. Trump moved to impose a temporary universal tariff and then said he would raise it, while also pursuing further investigations under national security and unfair trade practice laws.
That is why many countries are unlikely to repudiate existing trade arrangements with Washington, even after the Court’s decision. For major exporters such as Japan, South Korea and EU member states, access to the US market still depends not only on the removal of one class of tariffs, but on avoiding new sector-specific measures affecting cars, steel, semiconductors and other strategic goods. In practical terms, legal victory for tariff challengers does not remove the political and commercial risk of retaliation through other channels.
This helps explain why analysts have argued that the ruling changes the form of US leverage more than its existence. The pressure on negotiating partners may even increase in the short term if Washington uses Section 122 as a bridge while preparing more targeted actions under separate statutes. Administration’s post-ruling strategy includes exactly that combination: temporary across-the-board duties plus fresh investigative pathways for longer-term measures.
The legal ambiguity surrounding several recently announced trade understandings also adds to the caution. In policy circles, some of these arrangements have been described as politically driven, headline-level deals in which broad tariff outcomes were announced first and detailed implementation left for later negotiation. If the legal foundation of part of the tariff framework has now been removed, governments may seek tactical adjustments or delays rather than formal withdrawal. That approach preserves room for manoeuvre while avoiding a direct confrontation with Washington.
For the European Union, the issue is not only commercial. Any EU decision on tariff concessions to the United States sits within a broader geopolitical context, including transatlantic security and continued support for Ukraine. This makes an immediate rupture less likely, even if Brussels now has a stronger legal and political argument to seek better terms or sequencing. The Court ruling may therefore become a bargaining instrument in negotiations, rather than a trigger for cancellation.
At the same time, the ruling opens a second and potentially more disruptive front: the fate of tariff revenues already collected. The Supreme Court did not decide whether importers must be refunded for duties paid under the invalidated IEEPA-based regime. This question is now expected to move into lower-court litigation, likely centred on the US Court of International Trade.
The sums involved are substantial. Estimates cited in media and expert commentary vary, but they run into well over $100 billion collected during the period in question. AP reported that the Court left unresolved what happens to more than $133 billion already collected, while reporting elsewhere has suggested even higher estimates depending on the tariff categories counted.
That creates an economic and legal paradox. Some importers may have absorbed tariff costs, while others passed them on through higher prices. If refunds are eventually ordered, courts may face years of disputes over who bore the real burden and whether repayment to importers would amount to overcompensation in cases where costs were already transferred to customers. Business groups have already begun pressing for repayments, but legal analysts warn that any process is likely to be slow and contested.
There is also uncertainty over whether the administration could attempt to rebuild parts of the tariff regime through alternative statutes in a way that reduces or complicates refund claims. Even if such efforts succeed prospectively, they would not eliminate the litigation over past collections.
The Supreme Court ruling is therefore significant, but not decisive in the way many expected. It weakens one legal pathway for presidential tariffs, yet leaves intact several others. For US trading partners, the result is not a return to predictability. It is a shift to a narrower, more contested, but still highly coercive trade environment — one in which existing deals may survive, while the legal and financial consequences of the old regime remain unresolved for years.
