Canada has become America’s northern security threat

Canada’s failed policies are doing more than fouling American air. Summer across the Midwest and East Coast has again brought unhealthy and hazardous air-quality warnings from Canadian wildfires. Poor forest management threatens public health and daily life. Canada’s immigration policies pose a deeper and more lasting danger.

Most Americans still regard Canada as a polite northern extension of the United States: familiar, friendly, and strategically harmless. That view belongs to another era. Canadian Prime Minister Mark Carney has said that “nostalgia is not a strategy.” Neither is complacency.

America once regarded the northern border as its safest frontier. That assumption is precisely what now makes it dangerous. Nobody thought to watch it.

Canada is becoming one of America’s most underestimated national security vulnerabilities: a permissive northern platform through