He maintained control of the weapon and eliminated any threats to remove that control from him without harming any innocent people. Each person who was shot was attacking him with either a hand on his barrel or a firearm. His rifle never malfunctioned and he only missed 'Jump kick man' (an attacker that has never come forward or been found), Kyle face was being stomped into the pavement with big steal toe boots while shooting at "jump kick man". This is all clearly visable on the videos that are widely available. He shouldn't be on trial, and this should not be a debate.