It's not often that we can measure something like pro or anti-American political bias in American movies, but we can today because of a unique experiment conducted by Hollywood!
The reason why is because of the uneven level of quality of most movies, which can make it extremely difficult to make direct comparisons of a characteristic like political bias between them using the measure of how well they do at the box office. For example, one movie in a given genre might have good acting, but suffers from bad writing or poor direction. Another movie might have only okay acting and direction, but features really good writing.
That's often because different movies get made by different people, which introduces a lot of random elements into their production that can affect their quality, which in turn, affects their money-making potential. And then there's the matter of what audience the movie is aimed at - a movie targeted for teens will have a different box office performance than a movie targeted toward a older segment of the movie-going public.
But what happens when you put the same creative team to work behind movies that target the same basic audience demographic in the U.S., but are very different in their pro or anti-American political sentiment?
What happens is that you take out a lot of the randomness that might otherwise make a comparison between the movies produced by the same team invalid. You get a consistency of quality in all the other elements that can affect box office performance that makes it possible to measure just how much having a pro or anti-American political bias can have at the U.S. box office.
And that's exactly what we have today, thanks to the former Academy Award for Best-Picture winning The Hurt Locker and the current Academy Award Best-Picture nominee Zero Dark Thirty!
Both movies were made by same production team, including the director and screenwriter. Although they feature different actors, the overall quality of acting in The Hurt Locker and Zero Dark Thirty is also consistent, as measured by Academy Award nominations for the lead characters in each film.