WASHINGTON — U.S. President Donald Trump warned Friday that losing his administration's ability to tariff countries that treat the United States unfairly would be a "terrible blow" to the U.S., describing tariffs as an "overwhelming benefit" to America. Trump made the remarks in a social media post, as the U.S. Supreme Court deliberates the legality of Trump's use of the International Emergency Economic Powers Act to impose across-the-board, country-specific tariffs on America's trading partners, including South Korea. "Tariffs are an overwhelming benefit to our Nation, as they have been incredible for our National Security and Prosperity (like nobody has ever seen before!)," he wrote on Truth Social. "Losing our ability to Tariff other countries who treat us unfairly would be a terrible blow to the United States of America. Thank you for your attention to this matter!" Last month, Trump said that if the top court rules against his tariff policy, it would pose the "biggest threat in history" to U.S. national security. Trump has been using tariffs to encourage foreign investment, increas