re: "opposition to nationalism"
I would have thought any reading of 20th century history clearly demonstrates the evils of 'nationalism'. (By this I mean jingoism, der Volk, empire-building, etc. - Genuine patriotic love for one's own community is something else entirely.)
I don't need any '1940s communist' - or ideologue schoolteacher - to tell me that. It's just commonsense.
(I make no comment however on the main thrust of this thread, not being qualified to do so. Just thought I'd reply to that particular point)