I saw this on a website tonight – thought it was interesting. 

(discusses the evolution of looters after a disaster)

Looter+1: Don’t kill everyone, leave some alive to loot again later.

Looter+2: Plan to scare, rather than kill, your victims, so that they can continue farming and provide for your needs later. Dead victims can’t work.

Looter+3: Claim a territory and collect “protection” money/goods from the people in your territory. Tell them that in return for only taking one-third of everything they produce, you will protect them from “looters” who will take it all and kill them in the bargain. Punish anyone who holds out.

Looter+4: Call your loot taxes. You are now a government.