After the US Supreme Court ruled against President Trump’s import tariff measures, his first reaction (after harshly criticising the judges who ruled that he had exceeded his authority) was to announce another 10% global tariff. Shortly after, he threatened that the new US tariff would be 15% instead of 10%.

Officially, the only signed executive order says that President Trump imposes, “for a period of 150 days, a 10% ad valorem import duty on articles imported into the United States”. Given the volatility of the Trump’s Administration’s trade policy, it is all but impossible to predict, at least with any accuracy, what US tariffs will be when this period elapses.

However, what we do know is that the chaos and uncertainty surrounding them will make investors and businesses extremely cautious. The resulting slowdown in trade will have an undeniably negative economic impact that will be felt by everyone.

Read more: Trump hikes global tariffs to 15% as the fallout from Supreme Court loss continues

A nonexistent economic emergency

On April 2, 2025, which Trump dubbed “Liberation Day”, the president declared that the US was in an economic emergency that gave him a mandate to set tariffs at will.

To make this happen, Trump invoked the International Emergency Economic Powers Act of 1977 (IEEPA), which granted him the authority to use tariffs to address a national emergency. However, most independent........

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