I've been reading Tsong-Ka-Pa's commentary on Nargajuna, so "fundamental" appears to me more as "irreducible", "inherent", or "non-contingent" or even "soul". If we accept a "the sun rises" level of discourse as true, then "fundamental" as "basic to this level of abstraction" is just fine. But then what's the point? why not just say that? "Fundamental exceptionalism" seems to point to some irreducible element, some kind of God given soul that is above mere contingency.
The coastline/ocean/interior analysis is much more clear in its boundaries, says something specific not given to emotional/political vagaries. Of course these virtues are exactly what is being avoided in the phrase.
I find this discussion kinda vague. And maybe this comment covers no new ground, and is in general agreement with this post.
What unites the various beliefs "that the U.S. was unlike other countries is some fundamental way" other than there is something? Can Turner for example be said to be a proponent of the idea if he thought that America might be (ie that it's possible) loosing its "fundamental" exceptionalism? For that matter what's "was" doing in that quote rather than "is"? If it can be lost while life goes on, what does "fundamental" mean?
Every place on earth has exceptional geography. Certainly it's possible to imagine dystopias in which Anarctica has the most awesome geography from which to launch world domination, or at least survival.
Certainly incoherent ideas can be taken as true, and certainly such beliefs can have historical significance. But given the historical variety of what has been meant by AE, I don't find "awesome" to be particularly vulgar or historically unimportant.