President Trump is abusing powers that he doesn’t even have.

Article I, Section 8 of the Constitution of the United States indicates that the U.S. Congress—not the President—has the power to set tariffs.

“The Congress shall have Power To lay and collect Taxes, Duties, Imposts and Excises, to pay the Debts and provide for the common Defence and general Welfare of the United States; but all Duties, Imposts and Excises shall be uniform throughout the United States….”

“If the on-again, off-again tariff announcements by President Trump have struck you as unusual, that’s for good reason. Nothing like this has ever happened before,” according to Jeff Sommers in The New York Times.

“That’s the estimation of Douglas Irwin, a Dartmouth economic historian whose 2017 book, Clashing Over Commerce: A History of US Trade Policy, is the leading work on the subject. I called him for perspective. He told me that what we were experiencing was way outside the historical norm. One man alone has risked the first global trade war since the 1930s by raising tariffs to levels unseen for more than a century. The president’s actions, he said, represent a ‘big break with history.'”

“Even if Mr. Trump removes the tariffs — he announced a 90-day pause for some of the highest ones on Wednesday, while keeping a 10 percent base line for virtually all imports from around the world — his go-it-alone stance is a major departure. However the trade saga develops from here, the first skirmishes in a trade war, a dreaded relic of the Great Depression, have begun in the 21st century,” Sommers argues.

“The consequences are still unfurling, but the stakes are high. They include the possibility of a global recession and geopolitical shifts that may not be in the interests of the United States — all occurring because of the swiftly shifting decisions by the president of the United States.”

President Trump is clearly abusing the power that Congress has unconstitutionally delegated to him.

Jeff Sommer argues that “The U.S. presidency has always been powerful, but in the past, presidents were hemmed in by law, custom and politics. As the wild swings of recent days show, however, Mr. Trump is unaffected by most of those restraints. More than in the past, the direction of the markets and the global economy depends on the mood of the president.”

Further, President Trump has been accused of using his tariff decrees to manipulate global markets in corrupt ways that may benefit himself and his associates.

“Accusations of insider trading, market manipulation and corruption more broadly are being levelled at the White House as Trump switches tactics,” according to The Guardian.

“The timing of the US president’s social media posts and the subsequent huge share jumps has sparked accusations of market manipulation.”

The Guardian reports that “Trump said it was a ‘great time to buy’ just hours before he made a dramatic retreat on his trade war that led to big rises in stock markets around the world.”

“The Democratic senator Adam Schiff has called for an investigation, saying: ‘These constant gyrations in policy provide dangerous opportunities for insider trading.'”

“Schiff said he wanted to know who in the administration knew about the latest tariff ‘flip-flop’.”

“Thousands of investors are dedicated to tracking short-term movements in prices and it is theoretically possible that many close to key members of the Trump administration have made a profit from advanced knowledge of the president’s plans. However, no hard evidence has yet emerged that this is the case.”

Since the Trump administration controls all federal agencies that might investigate these accusations, we may never know. There was a sharp exchange during a Congressional hearing, however:

“The Nevada representative Steven Horsford questioned the US trade representative, Jamieson Greer, asking the representative during a committee hearing whether the climbdown was market manipulation,” according to The Guardian.

“‘How is this not market manipulation?’ Horsford asked, to which Greer responded: ‘No.’

“‘If it was always a plan, how is this not market manipulation?’ Horsford asked again.

“‘Tariffs are a tool, they can be used in the appropriate way to protect US jobs and small businesses, but that’s not what this does,’ Horsford said. ‘So if it’s not market manipulation, what is it? Who’s benefiting? What billionaire just got richer?'”

In a previous post, I provided some sources on the history of tariffs in the United States.

Sommer, Jeff. “How This Trade War Is Different From All Other Trade Wars.” The New York Times (11 April 2025).

Betts, Anna and Lauren Aratani. “US Stocks Fall Again as Ex-Fed Chair Decries ‘Self-Inflicted Wound’ of Trump’s Tariffs.” The Guardian (10 April 2025).

Inman, Phillip. “Why did Trump Retreat on Tariffs and is the Market Reaction Justified?” The Guardian (10 April 2025).

Irwin, Douglas. Clashing Over Commerce: A History of US Trade Policy. Chicago, IL: University of Chicago Press, 2017.

The Constitution of the United States is available at the National Archives website.