Trump Vows 10% Global Tariff after US Supreme Court Blocks Sweeping Duties

Segun Atanda/

The Supreme Court of the United States has ruled that sweeping tariffs imposed by Donald Trump were unlawful, prompting the president to pledge a new 10 percent global tariff using alternative legal powers.

The court decided by a 6–3 majority that Trump exceeded his authority when he used the International Emergency Economic Powers Act to impose duties on dozens of countries.

In its opinion, the court said the law did not give a president the authority to introduce tariffs.

“Our task today is to decide only whether the power to regulate importation, as granted to the president in IEEPA, embraces the power to impose tariffs. It does not,” the court stated.

The ruling represents the first major setback for Trump at the Supreme Court after earlier legal victories on several other issues, including immigration enforcement.

Speaking shortly after the decision, Trump criticised the judgment and said his administration would respond quickly.

He described the ruling as “deeply disappointing” and said he was “ashamed of certain members of the court”.

The president added that his administration would pursue other legal options to continue imposing tariffs on imports.

“Other alternatives will now be used to replace the new ones that the court incorrectly rejected,” Trump said during a press conference.

According to him, one option would involve imposing a 10 percent global tariff on top of existing duties already applied to imports.

Trump said the administration could rely on powers under the Trade Act of 1974, which allows a president to restrict imports for up to 150 days under certain conditions.

“We have alternatives, great alternatives. It could be more money, we’ll take in more money,” he added.

It was not immediately clear which current tariffs would form the basis for the additional levy.

The legal challenge was brought by groups of American businesses along with twelve US states. They argued that the sweeping tariffs were harming companies, trade relationships and domestic economic activity.

In its judgment, the court noted that during the half century since the law was enacted, no previous president had used the International Emergency Economic Powers Act to impose tariffs, particularly on such a broad scale.

Trump had introduced the tariff regime during what he called “liberation day” in April last year. The announcement triggered significant turbulence in global markets and raised concerns among American allies and trading partners.

Although the administration later softened some of the most severe measures, the United States ended 2025 with an effective tariff rate above 10 percent, the highest level recorded since the end of the Second World War.

Chief Justice John Roberts wrote the majority opinion.

Three justices dissented: Clarence Thomas, Samuel Alito and Brett Kavanaugh.

In his dissent, Kavanaugh noted that the ruling did not address whether the government must refund the billions of dollars already collected through the tariffs.

“The Court says nothing today about whether, and if so how, the Government should go about returning the billions of dollars that it has collected from importers,” he wrote.

Vice President JD Vance strongly criticised the ruling, describing it as “lawlessness, plain and simple”.

Writing on X, Vance argued that the decision would make it harder for the administration to protect domestic industries and strengthen supply chains.

He said Trump still had other legal powers that could be used to pursue the administration’s trade agenda.

Financial markets reacted cautiously to the news, suggesting that investors had anticipated the possibility of a legal setback.

The S&P 500 rose about 0.7 percent while the Nasdaq Composite gained roughly 0.9 percent by the close of trading.

The dollar index remained slightly lower on the day, and the yield on the two-year US Treasury note moved only marginally higher.

Market analysts said the limited reaction reflected expectations that the administration had already prepared alternative policy responses.

Jason Borbora-Sheen, a portfolio manager at the investment firm Ninety One, said the outcome appeared “largely expected” and noted that officials had time to plan their next steps.

Despite stock markets recovering since the original tariff announcement, public opinion polls indicate that many Americans believe the measures have hurt the economy.

The court’s decision now introduces fresh uncertainty over the future direction of US trade policy, particularly as Trump signals that new tariffs could be introduced under different laws in the coming months.

For trading partners and international businesses, the ruling may provide temporary clarity. However, the president’s vow to pursue a 10 percent global tariff suggests the broader dispute over tariffs and global trade is far from over.