This piece got me thinking (always a dangerous prospect). To summarize, a real-estate guy in Arizona sells 'protective services', which are actually highly-armed, paramilitary mercenaries, to private corporations.
This, of course, is a teeny bit less alarming than having official Government military forces protecting private assets, which, (not so) oddly, has happened before with the mine industry (but I digress). Let's leave aside the Fascism of government involvement for now.
No, I'm thinking about a future distopia, where wealthless masses and scarce food/water/power resources exist in a world of (largely-but-not-totally metaphorical) islands of (relatively) great wealth, luxuries, and comfort, protected by private armies of highly-armed mercenaries.
Isn't this where we are heading, with the astonishing stratification of society and wealth concentration? Instead of today's 'gated communities', where an attendant has to push a button to open the gate for your car to enter, imagine confronting a line of 'defenders' making it clear that you are definitely not going to gain access to the resources of the privileged few behind the walls.
As long as the Master can pay/feed/arm the troops, it's a sure bet that the angry/hungry masses at the gates will be 'handled'. The upside of this is full-employment for ex-military guys who have the perfect skills for the task at hand. The downside is archetypal.
It sounds like Europe in 1100 to me. Given the history of Greed, I expect this Wikipedia page will get bigger in time.
In other news, I have to get my car's AC fixed today - another heat wave coming next week.