President Donald Trump has stated that the United States would impose 10 percent tariffs on multiple European countries that oppose American control of Greenland.

In a new statement, Cato scholar Scott Lincicome said:

“Trump’s tariff announcement confirms what trade policy experts have long warned: First, because Trump’s trade deals are unilateral and non-binding, they can be easily changed on a whim and are unlikely to constrain his daily tariff impulses—impulses that have likely been emboldened by foreign governments’ efforts to placate the President. Second, today’s threat underscores the empty justifications for Trump’s so-called ‘emergency’ and ‘national security’ tariffs, which instead reveal the economic and geopolitical problems that unbounded executive power creates (and why the Supreme Court’s forthcoming ruling is so important for anyone concerned about constitutional constraints on the presidency). Even if the Court invalidates Trump’s emergency tariffs, however, it will still be up to Congress to amend the several other U.S. tariff laws that give the president similar tariff powers and, in the process, reclaim its constitutional authority over trade policy. Finally, for those who predicted that investment-stifling tariff uncertainty would fade in 2026, it’s time to revise those projections.”

To speak with Lincicome, please contact Emily Salamon at esalamon@​cato.​org.

For additional Cato resources on tariffs and executive trade authority, visit https://​www​.cato​.org/​ieepa