This just in from a Former Marine than I have the honor of being friends with.
Enjoy!

1. Be courteous to everyone, friendly to no one.
2. Decide to be aggressive enough, quickly enough.
3. Have a plan.
4. Have a back-up plan, because the first one probably won't work.
5. Be polite. Be professional. But, have a plan to kill everyone you meet.
6. Do not attend a gunfight with a handgun whose caliber does not start with
a '4.
7. Anything worth shooting is worth shooting twice. Ammo is cheap. Life is
expensive.
8. Move away from your attacker. Distance is your friend. (Lateral &
diagonal preferred.)
9. Use cover or concealment as much as possible.
10. Flank your adversary when possible. Protect yours.
11. Always cheat; always win. The only unfair fight is the one you lose.
12. In ten years nobody will remember the details of caliber, stance, or
tactics. They will only remember who lived.
13. If you are not shooting, you should be communicating your intention to
shoot.

Sweeeeeeeeeeet....I like #6, I pack a Springfield 1911 45 ACP on duty. Seems silly to have to shoot twice.
Dragon

Thanx for your reply Big John. I was a Hollywood Marine, '71-'75. Was stationed in Swamp LeJeune, NC, motor pool rat for the FMF, Operational Readiness Fleet. I was one of the MPRat that would tear apart the shot up, twisted hunks-o-sh*t that came back from 'Nam and try to reassemble something resembling a running vehicle.
M191 jeeps, PC carriers, duece & quarters and 5 tons... All the way up to the 10 ton missle carriers, also the Tank Retrievers and Ready Cranes. My fav vehicle was the 5 ton wreckers... almost unstoppable. Ya get stuck, just run out the cable and haul yer ass outta trouble!
Edge

aww, you left out the most important ones

Bring a gun. Preferably, bring at least two guns. Bring all of your friends who have guns.
If you can choose what to bring to a gunfight, bring a long gun and a friend with a long gun.

and the really, really important one

Your number one Option for Personal Security is a lifelong commitment to avoidance, deterrence, and de-escalation

I agree with ALL the above! Especially the A.D.D. Course, when all turns to poop, remember #3 & #4!
Edge

There is still some left out,
When all else fails be aware of your situation and stear clear of bad ones if possable.
And be ready for anything and expect the unexpected.
I was tought 2 in the chest, 1 in the head, then you know there dead.

sorry had to add them.