OR, Joss just came to the same logical conclusion that we did: Without the US military being involved (and with the government having
entirely different intentions toward the situation), Rhodes wouldn't be involved. It seems to me that comic book fans who saw the movie don't feel "disserviced" by it at all, and I'm pretty sure a lot of them are also fans of the
Iron Man movies. Don Cheadle's not only busy headlining his own TV show, but he's also got a recurring gig in the IM franchise, so he's probably fine about it. This movie packed in all it needed to and more for an introduction to the
Avengers. No War Machine needed. In fact, considering Iron Man already got 2 supporting players from his films featured in this movie (Potts and Widow), while Hulk and Cap got none, adding
yet another IM character would start to feel excessive, and probably bring about even more concerns of this seeming like "Iron Man 3" than it already gets.
Otherwise, to the rest of your post, I agree things did get a little overly hostile toward J. Howlett. I hope it hasn't chased him away for good.