There is a short but interesting article in New Scientist titled “Can complexity theory explain Egypt’s crisis?”
The article links to a 2008 New Scientist article which, unfortunately, is available only to subscribers. But since this complexity thesis is in accord with my own prejudices ( 
) I link to it here, and ask for comments.
Sounds reasonable, but it seems like a needlessly complex way of stating things.
Rising food prices always brings the threat of instability because it is one of the few shocks that disproportionately affects the urban power bases that physically and politically keep heads of state in power. The last round of global food price rises brought a round of political instability as well. People will put up with a lot, but if you can’t eat all bets are off.
My theory is that nothing in the whole world is as potentially dangerous as young single men. If you have a population with a large number of young single men, then you need to keep them occupied in one of three basic ways: work, play or war. If they’re poor they work, if they’re rich they party, drink and screw, and if they’re middle class they work during the week and play on weekends. Alternatively, they join (or are put into) the military, and either train or fight depending on if it’s peacetime or wartime. Trouble arises when you have lots of single young men and there are no jobs so they don’t work and can’t afford to party, and it’s been long enough since the last war that there isn’t room for them in the Army.