What are “American” Science Fiction Films?

Over at the AMC site, a reader asks how American science fiction films are different from science fiction films of other nations, and I reply, more or less, that I wonder if “American” science fiction films exist at all — as opposed to “Hollywood” science fiction films, which are not precisely the same thing. All will be revealed when you click through. And if you think I’m going about this exactly the wrong way (or miracle of miracles, think I’m exactly right), be sure to tell me in the comments over there.