Why worry about having to be ready all of a sudden? I'm always ready. We always drive with doors locked and lock our home doors when we're there. I always carry and if someone tries to rip my door open at a stop light they'll be looking down the barrel of a .45 or .40 S&W. After seeing a white truck driver nearly stoned to death after he was pulled out of his truck in LA during the riots I've got no problem pulling the trigger on somebody stupid enough to open my door.
Don't blame you got lost going to Newark airport one time and ended up in Harlan...I am sure I hit one of the guys who tried to stop my car by jumping at it and trying to stand in front of me....I ran every red light.