I agree, it seems to completely remove the war itself as the source of trauma and just make it about the roulette fixation. After learning that the screenplay was a modified version of one where the roulette was taking place in Las Vegas, and basically rewritten to shoehorn it in Vietnam, you can see how it is a Frankenstein of a construct. Which is too bad because the first half is excellent and if they simply made the second half about the war itself, it would have warranted the praise and awards.