Between 2017 and 2021, Donald Trump had the world on a precipice, bracing for his next move, gaming out whether his bluster was a bluff, an overture to a deal or a break with history, as he sowed mayhem to push adversaries off balance.

The president-elect’s threat to hit Canada, Mexico and China with new tariffs is already rocking business and diplomatic relationships and could topple the trade pacts he signed in his first term.