Neighbours with a long history
Canada and the United States share the world’s longest undefended international border, about 8,900 km including Alaska. Their bilateral relations are among the closest in the world, built on trade, security, culture and family ties. But the relationship also involves tension, because Canada is much smaller than its neighbour, with about one-ninth the population.
Former Prime Minister Pierre Trudeau described living next to the United States as being "like sleeping with an elephant."
From conflict to cooperation
| Period | Events |
|---|---|
| 1775–1783 | American Revolution; Loyalists move north |
| 1812–1814 | War of 1812: American forces invade British North America and are pushed back; First Nations allies such as Tecumseh play a key role; seen as a founding moment by many Canadians |
| 1854–1866 | Reciprocity Treaty: free trade in natural products |
| 1867 | fear of U.S. expansion after the Civil War helps drive Confederation |
| 1903 | Alaska Boundary dispute decided largely in favour of the U.S. |
| 1909 | Boundary Waters Treaty creates the International Joint Commission for shared waters |
| 1940 | Ogdensburg Agreement: joint defence planning |
| 1957–58 | NORAD created |
| 1965 | Auto Pact creates integrated auto manufacturing |
Economic relations
The two countries have one of the largest trading relationships in the world.
- Around three-quarters of Canada’s exports go to the United States.
- Canada is a top export market for many U.S. states.
- Supply chains, especially in cars, energy and agriculture, are deeply integrated.
Trade agreements
| Agreement | Year | Key features |
|---|---|---|
| Canada–U.S. Free Trade Agreement | 1989 | removed most tariffs between the two countries |
| NAFTA | 1994 | added Mexico; created a large free-trade zone |
| CUSMA (USMCA) | 2020 | replaced NAFTA; updated rules for autos, dairy, digital trade and labour; requires the three countries to review the agreement every six years, starting in 2026 |
A trade agreement lowers barriers. Debates over free trade have been heated: supporters point to growth and lower prices; critics point to lost manufacturing jobs and reduced policy independence.
Trade disputes
- Softwood lumber: a long-running dispute, with U.S. duties on Canadian lumber since the 1980s
- Dairy: U.S. objections to Canada’s supply management system
- Tariffs: the U.S. imposed tariffs (taxes on imports) on Canadian steel and aluminum in 2018. In 2025, broad new U.S. tariffs and the U.S. president’s talk of making Canada the "51st state" triggered a major trade dispute, Canadian counter-tariffs, consumer boycotts of American products, and a surge in Canadian national feeling.
Security and defence
- Both are founding members of NATO (1949).
- NORAD jointly defends North American airspace, with a Canadian deputy commander.
- Canada fought with the U.S. in Korea and Afghanistan, but declined to join the Vietnam War and the 2003 invasion of Iraq.
- After the September 11, 2001 attacks, Canada welcomed thousands of stranded air passengers, notably in Gander, Newfoundland. Border security was tightened, affecting trade and travel.
Culture and identity
Canadians consume enormous amounts of American media, music and products. To protect Canadian culture, governments created the CBC (1936), Canadian content rules for radio and TV (CRTC), and funding for Canadian arts. Many Canadians define their identity partly through differences from the U.S., such as public health care, gun laws and multiculturalism.
Key tensions
| Issue | Canadian concern |
|---|---|
| Sovereignty | economic dependence limits independent choices; Arctic waters such as the Northwest Passage |
| Environment | acid rain (resolved partly by the 1991 Air Quality Agreement), pipelines, climate policy |
| Defence spending | U.S. pressure for Canada to spend more on its military |
| Border | migration, drugs, security |
Continentalism, meaning closer integration, is debated against nationalism, which means protecting Canadian independence. Many Canadians also argue for diversifying trade with Europe and Asia.
Try it yourself
- Create a timeline of Canada–U.S. relations highlighting cooperation and conflict.
- Evaluate the impact of free trade on one Canadian industry.
- Debate: "Canada should reduce its economic dependence on the United States."
- Analyze how Canadian identity has been shaped by its relationship with the U.S.
Quick recap
- Canada and the U.S. moved from war in 1812 to close partnership.
- They share one of the world’s largest trading relationships, governed by CUSMA.
- They cooperate on defence through NATO and NORAD.
- Tensions include trade disputes, tariffs, sovereignty and culture.
- Canadians debate integration versus independence.