The film follows the life of Chris Kyle (played by a believable Bradley Cooper), from his youth to when he becomes "the most lethal sniper in U.S. military history" and how it messes up with his mind in that he can't leave the war behind. As you might imagine, there's a fair bit of gunfire and violence involved but Clint Eastwood seems to know his stuff when it comes to that. Having an adversarial sniper (no matter how fictitious) was a good idea too.
A most gifted killer.
I know I might draw some hate by writing this next part since it is about a real guy, but I can only hope that part near the end where he is playing around with a real gun (or even a toy one for that matter) at home, pointing it at his family members and then leaving it cocked on a shelf somewhere was made up. That is never cool or a good idea (eg. "hey, daddy could do it, why can't I?"), regardless of how much training you have.
Also the final action part where he puts his team in danger by deciding to try get vengeance. Wow. That could have ended verrrrrry differently.
The true pity for me is that by succeeding to "come back" from the war mentally was probably what does him in in the end, as I don't see how his paranoid version would have let anyone get the drop on him.
Anywho, as a film I give American Sniper three bullets out of five. While he did what was right by him and his family, I would not pay to watch a good soldier lose his edge a second time.