The U.S. Supreme Court has ruled a significant portion of tariffs imposed by Donald Trump as illegal, a decision that undermines a key aspect of his economic policy. Trump expressed strong disapproval, calling the ruling "terrible" and "an absolute disgrace," and subsequently issued an executive order for a new global 10% tariff effective February 24th for 150 days. This ruling invalidates "reciprocal" tariffs on most imported goods, excluding sectors like automotive, steel, aluminum, and pharmaceuticals. Economists estimate the average effective tariff rate will drop from 16.8% to approximately 9.5%, potentially leading to billions of dollars in refunds for businesses that paid these tariffs, with some states already seeking reimbursements for households. The decision also raises concerns about the U.S. government's ability to negotiate future trade agreements, as the flexibility provided by tariffs as a bargaining tool is diminished.