Any hope that U.S. President Donald Trump’s professed love of tariffs was a bluff vanished this week.

Less than a week after returning to the White House, Trump hammered Colombia with a 25% levy, a sanction that was quickly rescinded when that government backed down and acceded to U.S. demands about accepting deportees.

The speed with which the U.S. president reached for this tool — against an ally no less — is proof that his threats are not empty words. Trump is a pugnacious leader with no tolerance for dissent. It promises to be a wild four years.