Perhaps State Formation Should be Called Farmer Formation

 Pandora's seed suggests that farming was a terrible idea. Especially with the barely-husbanded plants that early farmers had access to, it is overwhelmingly likely that they were perfectly aware that it was a terrible idea. They knew farming made you sick, short, and weak. 

 My theory says they didn't have a choice. Wheat fields are hard to hide and ripen in sync, meaning the tax man knows exactly where and when to apply traitorous force. The local strongman realized wheat farming made taxation very difficult to evade, so they shackled a ton of slaves and forced them to farm wheat. Statehood causes farming. As it happens, although farmers are almost totally useless, farming does support population densities up to 100 times that of hunters. No matter how good you are at pre-gunpowder war and no matter how poor your enemy, you can't win a 1 vs. 100 fight.

 Consider the logistics. In a hunter tribe, not everyone can be a warrior, or even a hunter. Someone has to hunt for the warrior, and someone has to make spears and furs for the hunter. There's a lot of support infrastructure. I can imagine the 1 hunter waging guerilla war with impunity against the softling farmers, but it's not even 1 vs. 100, it's 1 vs. 200 or worse. He can barely kill them as fast as they breed.
 The farmers are such poor warriors that training them is irrelevant. Draft the lot of them, go full zerg rush, let the survivors work out how not to starve next winter. Conveniently the harvest can be stored and wait for the slave soldiers to return. Farmers can go from 100% farming to 100% warfare, paying the price of holocaust-level casualties. Hunter tribes can't transition to 100% warfare unless they plan to loot all their food - and even then, a healthy hunter will suffer terribly trying to transition to a farmer diet. Meanwhile, if war preparation damages the harvest, then, well, wage war until enough slave soldiers die that the harvest was big enough.

 China turned to rice farming because the irrigation works can be constructed with a single point of failure, allowing the chief parasite an even more extreme form of leverage. Bonus: the system is tamper evident. Hard to make a secret backup irrigation ditch. It's not rice farming => hydraulic empire, it's the fact the han precursors had the bright idea of a hydraulic empire, and imposed rice farming via defection.
 P.S. They scaled up the single point of failure strategy to the whole country, meaning when the parasite stuttered, the whole realm stuttered, amplifying small issues into catastrophes. Karmic debt for permitting a black government. 

 Perhaps northern europe is less treasonous because the winter is too cold and snowy to wage war. In the south, you can sow, guard the land, harvest, then campaign over the winter. Indeed, what else are you going to do with all these bored farmers during the cold months? In the north, sure you can war between sowing and harvest, but only by leaving your wealth exposed. Have to develop some measure of cooperative peacetime, because warfare is too risky.
 Likewise, it would seem pastoralists are less dysgenic because there's no time the herd becomes concentrated into a tiny, easily-guarded form. Can't go full zerg and follow up with full rabbit. The compromise between hunter health and cultivated population density is unfavourable to the agriculturalist.

 Early wheat taxers likely knew pasturing was better, but it makes taxation harder, so they eschewed it. When the tax man comes for your cow, you can harass him over the open meadows while driving your herd to flee. Farming security is only cheap too late, when the harvest is already in and stored in the silos.
 In response to farming empires, pastoralism arose and grew due to competitive advantages. 

 If you burn a wheat field, it's a one-step conversion to pasture. Doesn't matter how many farmers there are, partly because they suck so hard due to overcrowding et al, and partly because you and your herd can flee until they're too tired to chase, and then the farmers quietly starve at no further risk to you. What are they gonna do, trample the meadows? Which the herds already do?
 That is: farming is profane. Herding is sacred, at least to a degree.

 

 The slave farmers should have retained their honour rather than their lives. If they had demanded health and holy glory, the strongman would have lost. Cowardice snatches defeat from the jaws of victory.
 They didn't because Caino masochiens hates itself. The suffering was the point. Mere subtraction biology: maximize lives not worth living. 

 Herding would be even more obviously superior if the pastoralists didn't keep boinking the local holes and picking up imbecilic farming genes.
 One must wonder if there's an even more sacred form of cultivation, one that mogs herding as badly as herding mogs farming.