Technically, it only works because it looks very much like an accident. China and at least one dictator have accused the US of doing this on purpose, so the US has to prosecute and act all hot and bothered about it, otherwise it starts to look like an intentional leak.
China's case is particularly interesting. It's nearly impossible to criticize them directly for anything, since they just deny it, mirror the same criticism back, and then threaten some kind of economic retaliation for it. Their playbook is clear, and effective.
But this accidental Wikileaks release allowed the US to publicly say to the world all sorts of stuff about what our government really thinks about the Chinese government, and there's nothing they can do in response. It was an accident, US is embarrassed and pissed off, but it just so happens the collateral damage to Chinese government's PR machine (and various dictators and whatnot) was worse.
China's case is particularly interesting. It's nearly impossible to criticize them directly for anything, since they just deny it, mirror the same criticism back, and then threaten some kind of economic retaliation for it. Their playbook is clear, and effective.
But this accidental Wikileaks release allowed the US to publicly say to the world all sorts of stuff about what our government really thinks about the Chinese government, and there's nothing they can do in response. It was an accident, US is embarrassed and pissed off, but it just so happens the collateral damage to Chinese government's PR machine (and various dictators and whatnot) was worse.