A potential trade deal between the United States and Canada unraveled on Friday, leaving new 50% tariffs to take effect and deepening a rift between the Trump administration and its most important trading partner. The tariffs, applied at midnight, cover a wide range of Canadian goods, including steel, aluminum, and agricultural products, and are among the steepest the US has levied against a close ally in decades.

Negotiators had been working around the clock in Washington to bridge differences, but by late Thursday evening, both sides acknowledged that talks had stalled. The key sticking points: Canadian demands for better access to the US dairy market, US objections to Canadian auto parts tariffs, and disagreements over dispute resolution mechanisms within the USMCA trade pact. A senior White House official, speaking on condition of anonymity, said Canada had refused to make meaningful concessions, while a Canadian official countered that the US had moved the goalposts at the last minute.

Canadian Prime Minister Justin Trudeau, in a televised statement on Friday morning, condemned the tariffs as a violation of the spirit of free trade and vowed to respond with dollar-for-dollar countermeasures. Trade Minister Mary Ng warned that the US action would be met with a swift and proportional response, including tariffs on US goods such as orange juice, motorcycles, and bourbon. The Canadian government is also considering legal challenges under the World Trade Organization.

The tariffs come at a delicate time for the US economy, which is already grappling with elevated inflation. Economists at the Peterson Institute for International Economics estimate that the 50% levies could add up to 2% to the cost of Canadian-made goods for American consumers, hitting sectors such as construction, automotive manufacturing, and food processing. The automotive industry, deeply integrated across the US-Canada border, is particularly vulnerable. A Ford Motor Company spokesperson said the company was assessing the impact and hoped for a resolution as soon as possible.

Relations between Washington and Ottawa have been strained since President Trump first threatened tariffs on Canadian steel and aluminum in 2018. The USMCA, which replaced NAFTA, was supposed to bring stability, but this latest dispute suggests that the deal has not resolved underlying tensions. The failure to reach an agreement is a major setback for the administration, which had touted its tariff strategy as a way to force concessions from trading partners.

On the ground, the impact is already being felt. Canadian lumber exports to the US have been halted at several border crossings as customs officials begin enforcing the new duties. Dairy farmers in Wisconsin and New York, who import Canadian milk products, are scrambling to find alternative suppliers. Meanwhile, Canadian businesses are bracing for a slowdown. The Canadian Chamber of Commerce described the situation as a lose-lose proposition.

Looking ahead, the window for a diplomatic solution remains open. Both sides have indicated a willingness to resume talks, but no date has been set. The longer the tariffs remain in place, the more damage they will do to the economic relationship that supports over $600 billion in annual bilateral trade. The coming weeks will determine whether this is a temporary spike in tensions or the start of a protracted trade war.