Unfortunately it's nowhere near that easy. Some of the stories that overlap with nationalistic flamewar are well on topic for HN. This is one. The recent TSMC stories come to mind. Really there are many of them.

While not all comment-wars are flame-wars I know what you mean. I've been involved in a few. Trouble is, if the chinese trolls cause enough trouble that the mods are happy to let the thread vanish[1], the trolls have won. Scratch that, china has won, because there's a strong reek of high-level organisation behind it.

[1] Assuming that's what is occurring; I don't know.