Frank Kogan

very vague loose handwavey version of marxist "explanation" of ww1: the economic system (viz free market capitalism) led to intense unstable conflict between bourgy and proles in industrialised nations as of the 1840s-50s; the solution was COLONIALISM -- the nations in question set up empires as smash-and-grab raids on the resources of the third world, thereby buying off and semi-co-opting the working classes in said nations, defusing the "contradition"; HOWEVER, by accident of geography and uneven development, these empires were not evenly spread among the various nations, and latecomers (mainly germany) had to seek THEIRS in territories great britain and france had earlier decided were HANDS-OFF (viz the balkans, belgium, russia, etc etc) --- the result was a catastrophic high-tech war BETWEEN the advanced nations, even though it wasn't apparently in anyone's interest (bourgy or prole) in those countries... except of course that the need for hugely intensifed technological war production (and the mass destruction) created vast and powerful new market opportunities

so the argument was that a nation could be in the grip of its markets and corporations -- and that these were pushing it into a situation where the interests of its PEOPLES (not just working class) were entirely secondary, which meant that the wars-as-they-occurred (between nations) occurred as an "expression" [the word i used above, which is not ideal at all] of the class conflict at the root of the story, yet appear to manifest in a way which (as you are saying) exactly FAILS to map onto conflicts of economic classes