Does Canada Really Represent a National Security Threat?

Does Canada really represent a national security threat to the United States? Other than frequent cold fronts and the recent hot streak of the Toronto Blue Jays, it's hard to imagine America's northern neighbor and NORAD ally posing a threat to its American friends. But a recent investigation into the national security threat supposedly posed by China to the U.S. aluminum industry casts a wide net – one that could end up catching in its meshes Canadian producers who play a key role in an integrated North American industry. If nothing else, the case adds further proof that trade actions are often a matter of cutting off your nose to spite your face.