Typical for Hacker News posters (in general) to dislike the United States government so much that, despite having complained and worried and speculated about the sophistication of the NSA's online snooping for the last year in a half, they assume that the government couldn't possibly have obtained any evidence they didn't want to release to the public, instead trusting the high certainty of experts who have decided that it couldn't have been North Korea because the Korean region setting is for the South Korean dialect or the writing didn't have the right 'Korglish' errors or other such trivialities (those are both actual points that have been made).
It's not as if the claims in this article that the U.S. has successfully penetrated North Korean networks (to the extent they exist, anyway) should be any surprise; it would be highly surprising if they hadn't. One might imagine that while the North Koreans are not super advanced, they know enough about how to analyze and remove malware that it might be better to stay vague, even at the cost of appearing less credible, rather than disclose specifics of what communications you're able to intercept. Yet surely, just because the finger is pointing at one of the usual enemies, it must just be warmongering rather than reflecting reality.
(Yes, yes, WMDs in Iraq. It is certainly possible that the U.S. really is that incompetent and/or hawkish. I just don't think it's very likely.)