That was the thesis of "The Great Illusion", published in 1911. Basically, nation states would rationally avoid war, as it is pure downside, economically. Obvio

That was the thesis of "The Great Illusion", published in 1911. Basically, nation states would rationally avoid war, as it is pure downside, economically. Obviously it's at least insufficient. I think it's a totally naive view. Even if we limit ourselves to only thinking about rational actors, we must always ask about economic costs for whom. Nation states do not operate as a unit as a rational economic actor -- we must look at the competing actors within. One group could somewhat win, and another substantially lose, and that may net out to a negative -- it happens regularly. Many are clamoring for it right now -- a new Cold War against China.