oh really?.... there would be less violence if we banned guns, as if guns are the source of all evil and violence, and simply banning them would create a panacea in our land? The fault is not in the stars, dear Brutus,  but in ourselves. 

and with all due respect, it takes 3 to 5 seconds to react to a shooting attack. You have to first understand that you are under attack and then see where the shooting is coming from. In this case, the shooter seemed evident. If armed citizens were able to defend themselves, they would have directed return fire to the original target, provided they had a clear shot. Its not like the movies. In reality an armed citizen has to determine if he can offer resistance or if the more prudent course is to take cover. Since we are all stakeholders in the community and have our lives, liberty, and property on the line when we use lethal force to defend ourselves, we have to decide whether we are going to get involved or whether we are going to take cover.