Regardless of your hurt feelings you need some time to lick better, there's no doubt that your spammer friend is ignorant on that which makes up Nato and the significance of it's 'article 5. When, or if the US becomes involved with active military aggression against China, could you explain to him how Nato becomes a player?
And then how Canada will become ground zero too in the nuclear war that could follow?
NATO and Article 5 does not apply unless the US has been attacked. The closest US territory is Guam.