Cops carry guns to protect themselves, not to protect you.
Never let someone, or something, that threatens you get inside arm's length and never say "I've got a gun". If you feel you need to use deadly force for heaven's sake let the "first sound they hear be the safety clicking off", and they shouldn't have time to hear anything after that if you are doing your job.
'The average response time of a 911 call is over 23 minutes, the response time of a .44 magnum is 1400 feet per second.'
"The most important rule in a gunfight is: Always win and cheat if necessary."
"Don't forget, incoming fire has the right of way.."
"Make your attacker advance through a wall of bullets. You may get killed with your own gun, but he'll have to beat you to death with it, cause it's going to be empty."
"If you're not shooting', you should be loading'. If you're not loading', you should be moving', if you're not moving', someone's going to cut your head off and put it on a stick."
"When you reload in low light encounters, don't put your flashlight in your back pocket.. If you light yourself up, you'll look like an angel or the tooth fairy... and you're going to be one of 'em pretty soon."
"Do something. It may be wrong, but do something."