What makes states: walls and writing

An acquaintance suggested James C. Scott's Against the Grain might be of interest. We'd been discussing the benefits of small, local forms of self-government versus the large state. I'd recommended Paint Your Town Red, and she countered with Against the Grain.

The author is an American political scientist and his book investigates the formation of the earliest states. It covers the period 6,500 BCE to 1,600 BCE in the region of ""Mesopotamia, and in particular the “southern alluvium” south of contemporary Basra... heartland of the first “pristine” states in the world." I do like a history book, and although this is not my usual period, I thought the theory was intriguing; that the establishment of these early states was largely a coercive enterprise. Scott admits there's very little supporting evidence for this because "a great deal of archaeology and history throughout the world is state-sponsored and often amounts to a narcissistic exercise in self-portraiture", whereas if "you built with wood, bamboo, or reeds, you were much less likely to appear in the archaeological record".

I had no preconceptions about the subject, other than supporting the idea that small, local government is often preferable to large state polity. Here's what I took away.

1. Like other species such as beavers, ants, and bees, hunter-gatherers at some point began to modify their environment, so that "by 5,000 BCE there were hundreds of villages in the Fertile Crescent cultivating fully domesticated grains as their main staple".
2. The move towards domestication may have been brought about by a sort of 'ice-age', the "cold snap of the Younger Dryas (10,500–9,600 BCE)", which reduced "the abundance of wild plants". This theory is "hotly contested in terms of both evidence and logic".
3. Why it happened is less important than why it became entrenched, especially as domestication led to an increase in diseases. In addition, one might question how the early state came to dominate these centres of population. Were walls built for protection or confinement? Did writing develop as a means to record crop production and taxation?
4. As the state grew, it became necessary to 'enslave' people to maintain production for food and tax purposes. Scott quotes Ester Boserup: "when population becomes so dense that land can be controlled it becomes unnecessary to keep the lower classes in bondage; it is sufficient to deprive the working class of the right to be independent". Plus ça change. 
5. Early states often broke down due to disease, destruction of the surrounding eco-systems, wars and over-exploitation.
6. Barbarians have had a bad rap. A great many were not primitives. Rather they were "nomadic pastoralists" who required "sedentary communities as depots of manpower and revenue as well as trading outlets".

For those whose curiosity isn't sated by the book, Scott includes a large number of notes and a bibliography of suggested further reading. There's an index too. It was an easy read, if somewhat repetitive, but that's not a bad thing. The problem is in rating it. It's well written, an intriguing thesis, and I do like history, but this period is too long ago for me and too full of conjecture.