By "American science fiction" I am refferring to a particular genre of science fiction that, if I am not mistaken, only comes out of the United States. Prime examples of this that I have in mind are Mass Effect and Babylon 5. But I suppose Battlestar Galactica and Star Wars and on occassion, the various Star Trek franchises fall tick some of the boxes below (some more than others) as well as games like Halo, Wing Commander etc etc...
I hate writing essays and have a bunch to write that actually matter so I'll put my main gripes into bullet points and perhaps we can go from there if anyone wants to add anything or criticise anything.
*Humans are all typically "American". Similarly, Alien races are all typified by cultural stereotypes that sometimes almost seem if they are derived from stereotypes that are applied to cultures WITHIN humanity.
*The themes of such American science fiction tend to be political and/or militaristic with the Science fiction being the vehicle. Dont get me wrong though... I realise that there are other themes often present also but there always seems to be a similar political undertone. A sense that "freedom loving" Humanity is under threat from an outside political force. I dont think it takes a genius to connect the dots.
*Everyone speaks English! I know this is a common gripe that many have with such science fiction... but I wonder if it ever occured to the producers that in the future, ANY human language let alone English may not be the common dialect in the known universe. ESPECIALLY when humanity is a newcomer as it usually seems to be portrayed as.
*Whats with Starfighters and battles fought in visual range? Even today we can launch missiles from miles away without even having to see the target. Why do space battles seem like a step backward in time? I suppose it could be easy to explain away using some sort of sci-fi device but I think a more accurate depiction of space battle would be more akin to submarine, cat and mouse type warfare rather than WW2 carrier fleet battles.
Anyway... in saying all that, I liked Babylon 5 and Mass Effect and Im a huge fan of Star Trek Voyager (though this series is probably the furthest away from the above that I can think of). Just wanted to express my opinions on this sort of thing becoming cliche.
EDIT- Nothing to do with Japan I admit but since most of us are interested in Japan via an interest of other societies, cultures etc. And because I think this is a sharing of my experience of what I see to be a cultural phenomenon then I think this post is OK