Comment by jcstk

Religion is a subset of ideology, and both are a mechanism to recruit labor to fight and not the reason for conflict. Material isn't cheaper to buy, the "owner" of the material has all of the leverage - lock them in like a SaaS contract and them jump the price up, and the buyer can't do anything. Crops and slaves are no longer valuable as port worthy coast and natural resource deposits, but the fight is still over land and power.