Canadian Prime Minister Mark Carney confirmed that his administration prepared contingency plans for a potential United States military invasion, describing the scenario during an interview this week as an extreme tail risk driven by ongoing trade and tariff disputes between Ottawa and Washington.
Trade friction between the northern neighbors has intensified sharply in recent months. Earlier this month, Ottawa implemented retaliatory tariffs ranging from 15% to 50% on more than $20 billion worth of American goods, covering items such as steel, aluminum, wool, lumber, milk, T-shirts, and air conditioners. President Donald Trump responded by barring Canadian products from federal contracts. Those measures followed a decision by the US on Aug. 22 to impose 50% duties on an estimated $28 billion of Canadian goods, including beer, cheese, and electronics.
Trade Retaliation and Extreme Contingency Planning
That August round of tariffs prompted Prime Minister Mark Carney to issue a sharp public rebuke to reporters, declaring that his nation had been subjected to an unprovoked economic assault.
“We were attacked. You’re at war when you get attacked. We got attacked. That’s fine. We’ve got the reserves. We’ve got the resilience. We’ve got the plan. We’ve got the focus. We will respond.”
Prime Minister Mark Carney, via Nypost
In response to those comments, the White House took retaliatory steps of its own, signing an executive order to rename Lake Ontario as Lake America
and threatening further tariff hikes on Canadian vehicles, trucks, and auto parts effective January 1.
While speaking to the New York Times on Wednesday during his visit to New York for the United Nations General Assembly, Carney explained that preparing for worst-case geopolitical friction is a core duty of government leadership, even when the scenario remains unlikely.
“I think you have a responsibility in these roles to look at extreme tail risk. That’s just risk management. That’s not a base case, but it would be irresponsible not to.”
Prime Minister Mark Carney, via Townhall
The Canadian leader declined to discuss details of what those military invasion preparations specifically involved.
Historical Precedents Along the World’s Longest Undefended Border
Although the two nations share a long history of friendship and the longest undefended border in the world, the militaries of both countries have historically maintained contingency blueprints for cross-border conflict. Following World War I, Canadian military intelligence head Lt. Col. James Sutherland Brown formulated Defence Scheme No. 1,
outlining a hypothetical pre-emptive strike on the United States if relations between America and the British Empire deteriorated.
In Washington, the U.S. War Department developed “Plan Red,” a strategy that envisioned a lightning strike on the Nova Scotia port of Halifax, the seizure of power plants near Niagara Falls, and a three-pronged invasion to capture Montreal, the rail hub at Winnipeg in Manitoba, and the northern Ontario nickel mines. That plan was shelved when World War II broke out and remained classified until 1974.
Current force structures highlight a vast conventional asymmetry between the neighbors. The United States military maintains approximately 1.3 million active-duty service members across six branches, whereas Canada has just over 100,000 regular and reserve forces.
Shifting Diplomatic Alignment Toward Europe and Defense Diversification
Trade friction and political friction have pushed Ottawa to explore new international alignments. European Commission President Ursula von der Leyen recently proposed making Canada an associate member of the 27-nation European Union, a move that President Trump characterized as a potentially hostile act.
At the same time, Canada is pursuing efforts to decrease its strategic dependence on the United States. Carney outlined plans to diversify away from Elon Musk’s Starlink satellite network and noted that Ottawa is actively reviewing its planned procurement of F-35 fighter jets. Alternative defense options under consideration include Sweden’s Saab Gripen, with Carney emphasizing a need for aircraft that excel in Arctic conditions.
Direct Communication Channels Despite Breakdown in Trade Talks
Despite the escalation in tariffs and contingency planning, Carney noted that he still speaks frequently with Trump, including in the wake of collapsed trade negotiations last month. Describing their working dynamic as direct and efficient, Carney pointed out that both leaders maintain open communication lines to address disputes without diplomatic intermediaries.
“From my perspective, we have a good relationship in the sense that we can pick up the phone and talk to each other about issues. He’s direct. I’m direct in terms of where positions are. It’s much more efficient that way, and so you know that exists and that will continue to exist.”
Prime Minister Mark Carney, via Cnbctv18
Carney also stated that Ottawa remains open to securing a mutually beneficial trade accord with Washington, pointing to essential agricultural inputs such as potash—a core fertilizer ingredient—as a logical foundation for future economic talks.