This line of reasoning is insane to me. For the most part, police act as a deterrent against crime, not as an actual barrier. Police tactics are geared toward making them more of a deterrent, making their presence felt by everyone around as much as possible. So calling the police because you've just been robbed is not likely to achieve anything (I've had two cars stolen, and in both cases the police never achieved anything).
If police aren't a deterrent from car theft (as carjacking is a pretty common crime), then we are encouraging that behavior by doing nothing and calling the cops. Conversely, if the average person, during an attempted carjacking, opened fire on the attacker, it would be a major deterrent. There would be almost no repeat offenders (I have been shot at, and it is terrifying).
If police aren't a deterrent from car theft (as carjacking is a pretty common crime), then we are encouraging that behavior by doing nothing and calling the cops. Conversely, if the average person, during an attempted carjacking, opened fire on the attacker, it would be a major deterrent. There would be almost no repeat offenders (I have been shot at, and it is terrifying).