President Donald Trump raised the global duty on imports into the United States to 15 per cent on Sunday, doubling down on his pledge to pursue an aggressive tariff policy a day after the Supreme Court ruled much of it unlawful.
Writing on his Truth Social platform, Trump said that following a thorough review of Saturday’s “extraordinarily anti-American decision” by the court to curb his tariff programme, the administration would increase import levies “to the fully allowed, and legally tested, 15% level.”
Shortly after the court’s 6–3 ruling rejecting the president’s authority to impose tariffs under a 1977 economic emergency powers act, Trump had initially announced a new 10 per cent global levy by invoking an alternative legal mechanism.
At the same time, the Republican launched a personal attack on the conservative justices who joined the majority, criticising their “disloyalty” and describing them as “fools and lapdogs".
The decision marked a significant rebuke from the high court, which has largely sided with Trump since his return to office, and represented a major political setback by striking down his flagship economic policy that has unsettled the global trading system.
Sunday’s announcement is expected to heighten uncertainty as Trump continues a trade war he has used to pressure and penalise countries, both allies and rivals.
It is the latest step in a series of fluctuating tariff measures over the past year, during which rates on goods entering the United States have repeatedly been introduced, amended or withdrawn.
Under the law, the new duty is temporary and may remain in place for 150 days. A White House fact sheet said exemptions would continue for sectors subject to separate investigations, including pharmaceuticals, and for goods entering under the US–Mexico–Canada Agreement.
On Saturday, the White House said trading partners that had reached individual tariff agreements with the administration would also be subject to the new global rate.
### High court defeat
Saturday’s ruling did not affect sector-specific tariffs previously imposed by Trump on steel, aluminium and other products. Ongoing government investigations could still result in additional sectoral duties.
Nevertheless, it represents Trump’s most significant Supreme Court defeat since returning to the White House 13 months ago, despite the court’s broader record of expanding executive authority during his tenure.
Trump praised the three conservative justices who voted to uphold his authority to levy tariffs — Clarence Thomas, Samuel Alito and Brett Kavanaugh, the latter a Trump nominee — thanking them for their “strength and wisdom and love of our country".
He alleged that the six-justice majority, including two appointed during his first term, had been “swayed by foreign interests”.
“I think that foreign interests are represented by people that I believe have undue influence,” he said.
Wall Street shares — closely monitored by Trump — edged higher on Saturday following the decision, which had been widely anticipated.
Business groups broadly welcomed the ruling, with the National Retail Federation saying it provided “much-needed certainty” for companies.
During court proceedings, the administration had argued that companies would receive refunds if the tariffs were ultimately found unlawful. However, the Supreme Court’s decision did not address the question of repayments.
Trump said he expected years of litigation over potential refunds, while Kavanaugh observed that the process could become “a mess".
Several governments said they were examining both the ruling and Trump’s subsequent tariff announcement.
German Chancellor Friedrich Merz said on Sunday he would consult European partners to formulate “a very clear European position” and a joint response to Washington ahead of his visit to the US capital in early March.
Domestically, Pennsylvania Governor Josh Shapiro, a Democrat, wrote on X that it was time for Trump to “listen to the Supreme Court, end chaotic tariffs, and stop wreaking havoc on our farmers, small business owners, and families.”
