[L'article Riposte canadienne aux tarifs douaniers américains – voici l’essentiel  a d'abord été publié dans InfoBref.]

Tariffs on Canada, threats against Iran’s partners and bond market intervention show a president weaponising US power while making Americans poorer at home

Three moves in the last week have exposed the limits of Donald Trump’s economic bullying. The US slapped 50% tariffs on another $20bn of Canadian goods – then threatened the same rate on the cars, trucks, parts and steel that America Inc depends on. On Monday, the Treasury secretary, Scott Bessent, menaced Iran’s trading partners with exclusion from the US financial network, hoping that coercion can deliver what months of war have not. And as the costs of war, tariffs and pro-billionaire tax cuts helped send US bond yields higher, the Treasury stepped in to tame long-term rates. These are not contradictory policies but a gamble: that US economic power can be repeatedly weaponised without reducing others’ willingness to depend on it.

The Trump administration’s “D-day” sanctions are potentially the most consequential because they expose the scaffolding of American financial power. While markets shrugged off the immediate threat, that calculation might change were the US to target a major Chinese refinery or bank. Such an escalation could spark a trade war with Beijing. The US has leverage. But China has pressure points – especially farmers in Republican states – that make using it costly. In the long run, there is a price to pay. Nations hold one another’s currencies partly because they trust the political relationship. Mr Trump is testing what happens when they don’t.

A fundamental rupture in the values that have united North America is not a problem that can be wished away: this is a warning to the western alliance

The Canadians are exceedingly angry. I realise this can sometimes be difficult for foreigners to deduce, given our national struggle to express the full range of human emotion outside ice hockey riots. However, let me assure you that the prime minister Canadians saw take the stage on Saturday morning in the wake of the collapse in trade negotiations with the US was a Mark Carney practically vibrating with fury.

“You’re at war when you get attacked. We got attacked,” he said, in a rare press conference that was as candid and clear as he ever tends to be. “That’s fine … We’ve got the reserves, we’ve got the resilience, we’ve got the plan, we’ve got the focus. We’re gonna respond, we’re going to focus on what we can control and what we’re going to build.”

Jen Gerson is a Canadian commentator and co-founder of The Line. She lives in Calgary, Alberta