The other two are strictly political. One is Canadian, although it seems to have been overrun with ultra-right wing Conservative Albertan separatists, so it feels like here. The other is American, but has forums for other regions. It's userlist is likely 60% American, 10% Canadian, the rest European with the odd Aussie or Costa Rican. The last one is the most academic of the three, although I wouldn't say it's overly academic. This is one is easily the most colourful and honest.
Why?