Trump Tariff Strategy hits legal block after Supreme Court win

President Donald Trump’s proposal to impose a 50 percent tariff on imports from countries that supply weaponry to Iran is facing internal disagreement inside his economic team over how, or whether, it can be carried out under existing law.

On April 9, 2026, Kevin Hassett, Director of the White House National Economic Council, pointed to the 1977 International Emergency Economic Powers Act (IEEPA) as a possible legal basis for the measure. His suggestion comes after a Supreme Court decision in February that narrowed how the statute can be used in connection with tariffs.

U.S. Trade Representative Jamieson Greer has taken a different view, indicating that IEEPA is better suited to trade restrictions such as embargoes rather than import duties. The split highlights a central question for the administration: which legal mechanism, if any, can support a tariff tied to foreign security concerns without running into the limits set by the courts.

The Supreme Court’s ruling on February 20 stated that IEEPA does not give the president authority to impose tariffs without Congress approving them. The decision also invalidated duties that had already been put in place under that approach, reinforcing that tariff-setting power cannot be exercised unilaterally under IEEPA as interpreted by the Court.

The ruling did not resolve whether IEEPA could be applied differently during an active wartime situation. Even so, legal analysts have raised doubts about relying on that possibility in this case. Ed Gresser of the Progressive Policy Institute pointed to the lack of congressional authorization for military action against Iran as a key reason the wartime question may not provide a workable path for tariffs.

Officials said the administration is reviewing all available options to implement the proposed duties. The policy aim, as described, is to target imports from nations supplying weaponry to Iran, but the immediate challenge is procedural: the Supreme Court’s precedent suggests that moving ahead without congressional consent would likely trigger major legal challenges.

Any lawsuits could slow or block enforcement, potentially delaying the tariff’s effect on trade flows. The legal uncertainty also creates a practical constraint for businesses and trading partners, because the timeline and durability of any new duties would depend on whether the administration can identify a lawful route that survives court scrutiny.