A study was done in the recent past that analyzed wars, many of them civil wars, and the conclusion was of about 40 odd conflicts, only two (one was involving modern day Serbia as I recall) involved nations where the per capita income was over $3500. So if you give a person/family a "stake" - a chance or a position, well, you do the math.

In my local County Supervisor race, I was doing some research and one local political point (remember, all politics is local) was that if there was a conflict between party affiliation and a person being a homeowner, the homeowner part of a person usually won out over party affiliation.

The Last Sasquatch should also note that culture is a big factor too. I suspect Thai's are generally more happy than say, Ukrainians, though the latter have a higher income. Some of that is culture or national identity and some of it is not having to live where there is a lot of snow.