In reply to Khürt Williams.

I'll have to dig into it more deeply, but my presumption is that, despite the fact that some of the map covers beyond its borders, this is just talking about the United States and does not include Canada or Mexico. Some of the effects take into account older history, so despite current geopolitics, the effects can be cross border in some small cases. My guess is that there's also some blurring at some of the borders drawn on the map in question within the US as well.

I imagine that a similar effect could be seen within Canada based on it's colonial history with the French and others including the United States and its own indigenous peoples.