Canada - U.S. relations

Canada and the U.S. share the longest undefended border in the world. The two countries have a long history of being significant trade and military allies.

On March 4, 2025, U.S. President Donald Trump launched a trade war, announcing 25-per-cent tariffs on all Canadian goods, with energy and critical minerals facing a 10-per-cent tariff. This came after months of threats to use 'economic force' to annex its northern neighbour as the 51st state.

Since then, Mr. Trump changed the equation on everything from autos to potash, with Canada's retaliatory measures ramping up in response.