Top 12 American Prog Albums

Well, narrowing a multi-national group down to a single nationality is always going to involve some arbitrary simplification. For the record, I consider Weather Report and Talking Heads American bands despite the Austrian and British origins of their respective leaders, but Mahavishnu Orchestra is a special case because I see it as much more of a manifestation of the individual wishes of the band leader (this is reflected by how McLaughlin wrote virtually every song ever recorded by the band, and the fact that "Mahavishnu" was the name that McLaughlin adopted for himself after becoming a follower of Sri Chinmoy, so you could say he named the band after himself). Considering how the actual music fits in with the American jazz fusion tradition of the time, I do agree with you though that it's far more useful for historical purposes to categorize the Orchestra as an American band.

Whoops, forgot those ones on my list (and I'd also put the smiley star by Caravanserai! ).