Read the Introduction to Jack Goldstone's Revolution and Rebellion in the Early Modern World in which he talks about how waves of state failures typically accompany the coming together of several primary forces that sweep away weakened regimes in clusters throughout history. See, http://books.google.com/books?id=M-T9dR7nWDUC&pg=PA1&source=gbs_toc_r&cad=4#v=onepage&q&f=false
Whether you're a CIA analyst, or someone interested in the structural-functional causes of unrest, this is an indispensable and sensible guide to the study of revolution.
While Goldstone focuses on the coming together of population increase, rising food costs, and mobilization potential of popular groups such as churches and guilds, the prices component of rising discontent is largely traceable in recent times to spikes in world energy prices, which are closely correlated with food production and distribution costs. These tend to hit countries that are net energy and food importers. If you look at the map below of food as a percentage of household budgets one sees that countries that have experienced the with highest net food costs in the MENA are precisely those that have experience uprisings in the last couple years.
Put that together with the rise in political activism by religious groups, such as the Muslim Brotherhood, and the potential for state overthrow and civil war following energy price rises becomes enormous and irresistible, particularly as part of regional power struggles.
Click on the above image to launch a full-screen interactive map.
Source: USFDA Economic Research Service
http://davidxjohnson.blogspot.com/2011/02/fuelfoodfed-connection.html