War is one of those human activities that everyone condemns and almost every society practises. From hunter-gatherer bands to modern nation states, organised violence is never completely absent.
The magazine-article explanation is intrinsic aggression. Human beings, particularly young men, are capable of extraordinary violence. Aggression explains why wars can be fought but not why they are repeatedly chosen.
Start with economics. In the agrarian economies of antiquity and within feudalism, wealth consisted of land, livestock, slaves, tribute and control of territory. Acquiring resources by conquest was frequently easier than creating them. War was often the quickest route to enrichment for a ruling elite.
Factories are generally more valuable intact than looted. Within capitalist societies, where the state enforces property rights and monopolises violence, intra-elite violence becomes expensive and counterproductive. Markets absorbed many competitive impulses that previously found expression through force.
Yet war itself remains stubbornly present. States like to maximise security and revenue. Their freedom of action depends upon the resources of the economies beneath them: bigger is usually better.
(I say 'states' but of course, that's an abstraction: better to say that the material interests of very large numbers of people correlate with the size, power and resources of their own state apparatus.)
Not everyone sees this.
Much of the intelligentsia in advanced capitalist societies adopts a quasi-pacifist outlook. Media, academia, religious institutions and the cultural sector benefit enormously from internal peace and stability. Their members are largely insulated from the direct pressures of inter-state competition, concluding that war is simply a misunderstanding that wiser people ought to transcend.
SF author Isaac Asimov: "Violence is the last resort of the incompetent.
States inhabit a different world from individuals. Within societies there are courts, police and governments and politics. But no world authority possesses a monopoly of force: a state's military power is its decisive last resort.
War will evolve. Humans may increasingly disappear from the sharp end of the battlespace, replaced by machines acting under human direction. Incentives, however, remain unchanged. As long as resources are scarce, states will compete and war will remain.
