He did what he had to to "Live to fight another day".
His call was one that wont make the anti gun crowd happy, I can hear them now "He didnt shoot because he was too injured.". No, actually he was concerned about his life and the armed threat was no longer a threat to him, losing blood was. My guess is, if the armed threat had returned, he would have defended himself, thats why he carried, not just to unbalance his hip!
Now to return to the threat that caused this, the nutcase with the Airgun! If that POS doesnt spend the next 40 years in prison doing hard time, evil wins again! I dont care if its a BB Gun or a cannon, assaulting an innocent Human with a weapon should carry the max possible term every time. Unfortunately for us, he will likely get 6 months in a terrorist training camp (jail), some meds that stabilize him (while he takes them) and probably all kinds of social services assistance to reintroduce him back to society where he will do it again and again....