Overview
Less than two months after the US declined to extend USMCA for another 16 years, a trade war is escalating between Washington and Ottawa, whose trade relationship is close to $900 billion. Tit-for-tat retaliation over recent tariffs threatens to eliminate thousands of jobs and raise costs for businesses and consumers in both countries. With bilateral trade talks between the US and Mexico set to continue in September, the US-Canada trade tensions also threaten to reshape the broader diplomatic balance in North America amid ongoing discussions over the future of USMCA.
In a turbulent week, US President Donald Trump announced a deal last Tuesday night, just hours before 50% tariffs on $20 billion in Canadian imports were due to take effect. Trump’s three-day extension allowed more time to iron out the agreement, but talks collapsed just before the Friday deadline. Canadian Prime Minister Mark Carney instructed negotiators to walk away from what he described as a “bad deal” for Canada, which reportedly would have included restrictions on Canada’s ability to make trade deals with third countries. US officials argued that the package would have placed Canada in the most favorable tariff position of any major exporter to the US. On Saturday, Carney gave a defiant speech to Canadians, described the US actions as an “attack,” and announced that Canada would retaliate against the US with dollar-for-dollar tariffs due to take effect September 8. The Trump administration has since threatened new 50% tariffs on Canadian autos to take effect on January 1, 2027.
The Failed Interim US-Canada Deal
The interim deal on the table ahead of the Friday deadline primarily broke down over misalignments around automobiles, alcohol, metals and dairy. In metals, the reported package would have reduced US steel and aluminum tariffs from 50% to 25%. In automobiles, Washington was reportedly prepared to cut its Section 232 tariff on Canadian cars and light-duty trucks from 25% to 15%, while Canada sought a 10% rate (and additional relief for Canadian-built medium- and heavy-duty trucks).
After the breakdown of talks on Friday, the US Trade Representative said that the proposed deal would have also included an announcement of formal USMCA negotiations between the US and Canada. The total breakdown of talks over the weekend could be interpreted as a strategy to strengthen the US negotiating position for future talks, but Canada’s defiant response has triggered a cycle of escalation and indicates that Canadians are willing to absorb some economic pain over accepting an unfair deal.
US-Canada Trade Dispute Clashes with USMCA Terms
As the US-Canada trade war intensifies, the new tariffs target some sectors that were previously protected under USMCA, casting doubt on the legality of the measures as well as the ongoing USMCA renewal negotiations. These tariffs stack on top of the Section 232 tariffs on steel, aluminum and copper, which Canada is also retaliating against. The new 50% tariffs on Canadian goods that took effect on Saturday were originally announced on July 20 under the authority of Section 338 of the Tariff Act of 1930, which authorizes levies against imports from countries that discriminate against US businesses.
The White House has accused Canada of discriminating against US commerce, particularly automobiles, alcohol and dairy. Since April 2025, Canada has imposed a surtax on some US-made vehicles and reduced duty-free quotas for automakers who shifted production out of Canada. Every Canadian province but two restricts the sale of American alcohol, resulting in an 81% decline in imports from March 2025 to February 2026. This is the first ever use of tariffs under Section 338 authorities. It is expected to be challenged in US courts, which struck down IEEPA tariffs in February.
When the US failed to confirm its intent to renew USMCA by the six-year joint review deadline on July 1, the agreement remained in effect under an annual review process. This means Article 2.4 of USMCA, which prohibits parties from increasing existing duties on originating goods, still applies. While domestic laws take precedence over international treaties under US law, the Trump administration may struggle to prove in US courts that Canadian policies discriminated against US commerce.
US-Mexico Talks Advance, but Core Disputes Remain
Compared to Canada, Mexico has been more proactively engaging in trade talks with the US. After three bilateral rounds from May to July, the US and Mexican governments have agreed to meet for a fourth round in Washington in early September. The latest discussions covered automobiles, steel and aluminum, economic security, labor, agriculture, electronic payments, and measures intended to prevent non-parties, especially China, from capturing USMCA benefits. Mexican Economy Minister Marcelo Ebrard has pointed to progress on metals and replacing Asian imports with North American production, but there is no completed agreement.
The principal dispute is on automotive rules of origin. Washington has proposed requiring vehicles to contain 50% US-made content to receive preferential access. Existing USMCA rules instead require 75% North American content and do not reserve a fixed share for any individual country. Mexico regards a US-specific floor as a fundamental change to the regional production model and reportedly will not accept even a small national requirement. US negotiators have asked Mexico to propose alternatives that would move more automotive production into the US, reduce Asian components, and narrow the US trade deficit.
The two sides are also bargaining over new sourcing obligations and existing tariffs. Mexico wants relief from US Section 232 duties of 25% on automobiles and 50% on steel and aluminum before accepting further concessions. Washington, however, has indicated that at least some industrial tariffs may remain, potentially at preferential rates. Reported US ideas have also included expanding the automotive “core parts” list to impose tariffs on major electronics modules now largely made in Asia and favoring North American steel. US negotiators also asked Mexican officials to impose tariffs on steel and aluminum originating outside North America in an effort to synchronize actions against Chinese goods. These measures could strengthen regional sourcing but would also increase compliance costs and force suppliers to redesign established production networks.
A comprehensive settlement appears unlikely in 2026. US Trade Representative Jamieson Greer has instead sought an interim arrangement with Mexico by year-end, leaving difficult revisions to automotive rules, labor, and environmental provisions for 2027. Greer has also linked progress to issues outside the trade agreement, including border security and Mexico’s compliance with the 1944 Water Treaty.
Canada and Mexico Coordinate but Negotiate Separately
Canada and Mexico are conversing, but there are no formal bilateral negotiations comparable to their separate talks with Washington. Prime Minister Mark Carney and President Claudia Sheinbaum discussed trade developments on August 20, emphasized the need to renew USMCA as soon as possible, and agreed to remain in close contact. Although their interests overlap, they announced neither a common negotiating position nor a bilateral process for revising the agreement. Both want to preserve USMCA’s trilateral structure and avoid US demands that divide regional supply chains.
US-Canada and US-Mexico bilateral packages could reduce sectoral tariffs or establish country-specific economic-security commitments, but they cannot rewrite USMCA’s core trilateral rules. Article 34.3 requires the parties to agree in writing to treaty amendments and complete their applicable domestic approval procedures, while Article 34.7 allows all three governments to extend the existing agreement at any point before it expires.
Geopolitical Context and Economic Implications
For both Canada and Mexico, diplomatic disputes with Washington are threatening progress on trade negotiations. Mexico’s initially compliant approach with President Trump has shifted to increasing confrontation as the US has targeted Sheinbaum’s Morena party with indictments and visa revocations. Canada, however, has taken a particularly defiant approach as the only US ally, and one of only two countries in the world, to retaliate against US tariffs. While the EU and the UK opted to accept US trade terms with tariffs baked in, Carney has followed through on his vow earlier this year to lead “middle powers” in standing up to global superpowers, even if it means paying a hefty economic price. Other US allies, including Mexico, will surely take note of how Canada’s strategy unfolds, reducing incentives for the Trump administration to back down.
The economic effects of the US-Canada tariffs could extend beyond the immediate value of the goods subject to tariffs. US importers initially pay the duties, but the burden is likely to be divided between US businesses and consumers through higher prices and Canadian exporters through lower margins, weaker orders and reduced production. Canada is more exposed at the aggregate level, while US losses would likely be concentrated among downstream manufacturers, construction firms, consumers and border regions. While both the US and Canada stand to lose from the escalating trade war, Canada stands to lose more. In the long term, Canada could see the elimination of thousands of jobs if the tariffs remain in place.
