Canada’s retaliation tests the limit of American power under Trump

But power has limits. Trump’s second term has been a continuous test of those limits – and, at times, a lesson in finding exactly where they are.

While obvious differences exist between a shooting war in Iran and a trade dispute with Canada, the lessons are not dissimilar. In both, the US faces a counterpart that, despite having far less overall power, retains the means to retaliate.

For Iran, that leverage lies in targeting US allies and disrupting global commerce by threatening maritime chokepoints like the Strait of Hormuz.

Canada, for its part, is beginning to test its own ability to inflict economic pain. Tuesday’s targeted tariffs mark a first step. Future measures could include restricting US access to Canadian energy and critical minerals, alongside consumer boycotts of American goods.

“As the broader world shifts into a more economic security theatre, you see this game of chokepoints and leverage angles continue to pan out across supply chains,” said DeLong. Countries just have to look for them, he added.

For the moment, clear exit ramps are scarce. Trump has escalated his rhetoric, repeatedly accusing Canada of “ripping off” the US, while Ontario Premier Doug Ford fired back by telling the American president to “kiss my ass”.

“Every time we push allies and partners away, I think we incentivise them to look for new relationships and new partnerships rather than trying to acquiesce to US demands,” said Imran Bayoumi, deputy director of the GeoStrategy Initiative at the Atlantic Council.