Well, it does sound like this is playing out differently than when Chinese or Korean hackers go after Japanese sites. Essentially the read I get is that it's more organized and more professional. (Although as the article notes, there's certainly some capacity being held in reserve). I could be wrong on that.

So I don't doubt that there's some plausible deniability involved. But it sounds like this is being done by someone that has purposefully developed some cyberwarfare capacity. I'd tend to think that implies some level of government ties.