While watching the video did you notice clean and spotless the white cloth material between the terrorist in question and the already-dead one next to him?
It certainly had not been used as a bandage, and the worn clothing was dark colors.
In this Marines boots, I would have been compelled to surmise that this was another surrender-to-kill ruse (ESPECIALLY upon sudden movement), as has been the norm in Fallujah.
This Marine is guilty only of being alert and ready, IMO. The reporter might have been killed were it not for this Marine.
He was shot and wounded in the face the day before by a terrorist pretending to be injured! He also lost a buddy in the same assault who was killed when he attempted to move a booby trapped body.