Exposing government corruption (and sketchiness) isn't really the best area to apply black-letter law though - it is usually going to be illegal; governments routinely try to stop people publishing embarrassing information.

If a whistleblower can't intend to get information of a government network, how are they meant to make an allegation with some substance behind it? Are they meant to have unsubstantiated word of mouth? We had that for years with ECHELON, the moderate middle just didn't take any of it seriously until the breaking-the-law levels of leaking happened (yes, the legal details are different with Snowden, but the strategy is very similar - leaker gets hit with incidental charges).

The argument here seems to be that while in theory whistleblowing would be OK; none of the ways to attempt a credible whistleblow in the real world are legal. There is a lot of disagreement in this article's comments about what the law says, so it isn't obvious how a whistleblower, who could be anyone here, is meant to follow the details of what they are and are not allowed to attempt.

Assange isn't even a US citizen, so he isn't expected to know US law. Functionally, all this rigmarole is to ensure that if the US government does something sketchy or even illegal then any foreigner who talks about it is legally subject to one of the US's famous black-bag-over-the-head abductions. The charges seem to be independent of what he leaked.