The 2 Protective service teams were pulled out 2 "WEEKS" prior to the attack.
Look at the bright side. This probably saved their lives. Even if they sent in more marines, they would only have rubber bullets and bean bags against an angry mob and AlQaida with automatic weapons and RPG's. The sand fleas also dumped diesel fuel and set it ablame to smoke them out. Then picked them off as they tried to escape through a window.