The problem is that most Americans are the descendents of the people that arrived, displaced the native population, took their land and exploited it's natural resources.
So naturally they are wary of people coming along and doing the same to them.
I know I shouldn't feed the trolls, but I have to ask: do you really think there were no indigenous peoples in Canada when the French and English came to settle there? Just pristine wilderness?
So naturally they are wary of people coming along and doing the same to them.
This doesn't really apply to Canada.