In the olden days (like, a couple of years ago) classified documents would get leaked to newspapers. The newspapers would take a look at them and publish them in excerpt alongside an editorial talking about how they thought long and hard about whether it was in the public interest to publish this particular document and blah blah blah. As I understand it, based on my reading of the law, they were technically committing a crime by doing so, but the authorities never bothered to pursue prosecution against the media outlets and just prosecuted the original leaker. Why not? I don't know, maybe because responsible publication of leaks is acknowledged to be a good thing, or maybe because it's not worth going to war with anyone who buys ink by the gallon.
Wikileaks, on the other hand, will publish huge swathes of documents in a much less restrained manner than the New York Times would. It's concievable that they can be charged.
As far as I know, the law states that it's illegal to pass along classified documents, and it doesn't restrict the applicability of this law to the people who were supposed to have the documents in the first place.
Note that this does not apply to Bradley Manning or others who may be sources and who may have committed crimes in passing classified information to uncleared people. But as much as our political elites might wish it; embarrassing the government is not a crime.
International law can be very quirky (IANAL, but my work sometimes requires me to deal very directly with particular specific aspects of international law). Much of it comes down to precedent: if you can enforce a claim consistently for a long enough time, it becomes accepted and legitimate international law, which is the reason for the U.S. military's Freedom of Navigation (FON) operations. Conversely, if you allow others to regularly violate your national sovereignty in a particular manner without responding (even if only by formal diplomatic protest), then those particular rights may come to be accepted as no longer belonging to your nation.
A meta-observation: I've noted that posts saying, "he can't be prosecuted by the U.S." are generally getting many upvotes, while posts explaining how and why he could (not that he SHOULD, just that it's possible) are getting few or none. I can't know what other people are thinking, but it seems to me that people are voting based on what they would like to be true, rather than on what actually is true.
And even in this specific case, in espionage cases, the US can choose to prosecute and basically abduct anyone in the world they want, provided they're willing to put up with the political consequences. Not saying it's right, but if you think you can spy against the US (or many other countries) and face no consequences because you're not a US citizen, you might be in for a nasty surprise.
And yes, the U.S. can kidnap him and bring him into U.S. so they can charge him with U.S. law...but they can't charge him in another country under U.S. law and expect him to get arrested...not unless they go through the whole extradition thing.
But that's like saying, you fall under Chinese law, because they might send a hit squad to take you out for breaking their laws.
Yes might generally equals right internationally, but for now they are trying to put up the pretense that U.S. cares about foreign relations.
The people who abducted the suspect might be operating under USA law, and they might not be guilty when they go to the USA. However just because it's legal to do it in USA doesn't mean it's legal in the country they do it in. They would still be breaking the law in that country. Would you like if a person broke a USA law while in the USA and then said "But it's OK, it's legal under Irish law?"
To the person who posted this and those who upvoted this: you have power over the quality of the conversations on this site. Please give some thought to how you use it.
And remember, he is an Australian citizen so the whole treason thing doesn't apply.