I think this will be the greatest. two-legged physical threat we will face during a TEOTWAWKI  situation. Not terrorists. Not UN troops. Not marauding bands of looters. Not even KKK members or Neo-Nazis. It will be Mercenaries. Mercenaries like the Blackwater USA  security group hired by our government leaders as “security contractors” in Iraq. Mercenaries that are not held under Congressional or Military review, not held liable for their actions, and have no territorial or family ties like National Guard units. This YouTube clip , and this one  [show who I’m talking about.]
Read about the Thirty Years’ War  in Europe. Unemployed mercenaries roamed the countryside, killing, plundering, burning. The local armies were too weak too stop them–After all, that’s why they were hired to fight in the first place! Once they were let loose, they could not be reined in. I strongly believe the mercenary contractors our government hired with our tax dollars will become a Frankenstein someday that will turn on it’s own creator. A personal Praetorian guard answerable only to the highest bidder. – Ron S.