The timing is significant. Washington's effort to recalibrate its relationship with China depends in part on closer co-operation with its two largest trading partners. Introducing uncertainty into North America's economic framework risks undermining that strategy.

As Arturo Sarukhan, Mexico's former ambassador to the US, put it, in World Cup terms it would be "a huge own goal".

As a result, the 1 July virtual meeting between the three countries, once seen as a potential flashpoint, proved subdued.

The US has begun formal talks with Mexico and remains in contact with Canadian officials, suggesting negotiations are proceeding without the expected political drama. And with midterm elections approaching, analysts expect that calmer tone to continue.

Prime Minister Mark Carney has said that he won't rush to sign a bad agreement - but is ready to cut a deal if the right one arises.

US-Canada Trade Minister Dominic LeBlanc said on Thursday that Ottawa's focus was now on "substantive discussions" over current US tariffs on Canadian steel, aluminium, autos and lumber.

While the USMCA has sheltered much of the continental trade from Trump's tariffs, those sectors in Canada are struggling under US levies ranging from 10% to 50% on select sectors.

The decision not to renew the pact now starts a 10-year countdown. If no extension is agreed by then, the USMCA will expire. For now, however, annual reviews and steady diplomacy have replaced the brinkmanship many once expected.

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