Know what is behind you, and pay particular attention to anything out of place.
Never assume that simply having a gun makes you a marksman. You are no more armed because you are wearing a pistol than you are a musician because you own a guitar.
What are we going to do if citizens are disarmed, and the government doesn't obey its own laws?
Blessed are those who, in the face of death, think only about the front sight.
Pick up a rifle and you change instantly from a subject to a citizen.
The only acceptable response to the threat of lethal violence is immediate and savage counterattack. If you resist, you just may get killed. If you don't resist you almost certainly will get killed. It is a tough choice, but there is only one right answer.