China wields formal control where in the US this is achieves via peer pressure and social manipulation/control. Anytime something shocking is revealed reporters end up losing thier jobs, sometimes be suicided or at worst end up like Assange.
HN is for the gratification of intellectual curiosity, and political argument—especially the flamewar kind, which it inexorably degrades to—is destructive of that.
I generally only comment on issues I know about. Outside of technology, history and civics is a focus of mine, hence the comments.
Perhaps deleting comments like the parent (made on a throwaway account, apparently) would be a good idea. It would stop folks like me who feel compelled to reply to perceived propaganda from doing so.
The alternative is for everyone who feels strongly about political issues to create throwaways for such HN discussions (see parent), to avoid retribution on their main accounts. I doubt that's a world you'd want to moderate, or that I'd want to live in. (Not suggesting I'd go in for such sock-puppet account shenanigans, but it's the limiting case that comes to mind.)
Anyway, I suspect political stories will always provoke political discussion. If you'd prefer not to have this on the site, I'd humbly suggest flagging and removing such stories.
EDIT: Your point about flame wars is well-taken, however. I could certainly have highlighted the history and facts of American press freedom in a more constructive way here.