The only negligence was that they did not count on the Navy Seal/CIA guys coming and messing up their plan. Obama needed to show that he could be tough on Islam. He planned to have the Ambassador kidnapped and then he would get tough on the terrorists and they would give the Ambassador back. Obama a hero, election in the bag. He stripped away all the security to make it easy. Problem was that some Navy Seals showed up and started kicking some Muslim butt. Terrorists figured they were set up and the real plan was to wipe them out. They thought that Obama was trying to be the hero by defending the Ambasador. Things spin out of control, Ambassador is abused and killed Muslin style. Obama and Hillary have to go into spin and lie mode. It seems to me that the facts of what happened seem to fit well into this scenario.
As you say...