What? I'm Canadian. I guess I'm American in the sense that I live in the Americas, although such a geographic concept is most likely beyond you. Further, was that an insult? As someone's pointed out, this is a strawman attack, a classic logical fallacy, or, more generally, a non-sequiter.
Colloquially speaking (and this is for you, Deon), it means you don't know what the fuck you're talking about.