Why are films today based more on what could happen?...

           My question for this post is "Why are film today based more on what could happen? Unlike movies from around five or so year ago which were based on true stories. I suppose my question sort of points towards war movies. About five or ten years ago movies would come out being based off of recent happenings around the world such as, Black Hawk Down. Today you see more war/battle movies based on false events such as Battle: LA or Avatar. Is it that there just hasn't been any major events that a movie could be made out of, because I find that hard to imagine with all the talk about Iraq and what not. Or could it be that these types of movies don't attract as big of a audience as these fictional war movies do. I mean I can understand why some people would rather go see a movie about fake aliens taking over the world rather than a movie based on American soldiers being killed. To find an answer to this question, I will need to search a bit an try to find answer based on filmmakers and the audiences from both types non-fiction and fiction. I'll try and keep this updated with answers I get.