So, here's my defense plan for Canada. Basic philosophy: it is unsafe to wait for an attack.
1. Secure public confirmation from NATO that Article 5 applies even if the aggressor is also a NATO member.
2. Send an ultimatum to Washington demanding a public acknowledgement by the President of Canadian sovereignty and reconfirmation of non-aggression towards Canada.
3. In the absence of that acknowledgement, sever diplomatic ties, close the borders, and embargo trade in either direction.
[1/n]