The Supreme Court will hear oral arguments Wednesday over whether a law allows President Donald Trump to implement a worldwide tariff regime, in a case experts and lawmakers said ultimately could undermine Congress’ foundational power over taxation.

The Trump administration is set to urge the justices to find that those tariffs are within the powers that Congress gave to the presidency in an emergency economic powers law in 1977, with huge issues in the balance, including billions of dollars in federal tariff revenue and trillions of dollars in international trade.

The legal questions hinge on the wording in the law around regulating trade and declaring emergencies, how specific Congress must be when delegating large powers to the executive branch and whether Congress can turn over its

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