To give more of what I'd perceive an our general "American" point of view on this, is that the general public is quite alright with all manor of whistle-blowing and fighting injustice, etc, but we have a few 'sacred cows' in the public discourse that get special treatment (or collective myopia depending on your politics) and the military is one of them. In other words releasing internal memos from some politician is questionable or perhaps partisan but releasing classified military documents will get you a quick trip to the bottom end of public opinion from nearly all members of the Republic.
Eh, sorta.
Like I said, the New York Times, Aviation Week, the Washington Post, etc publish classified material, including military secrets every so often and so long as their source isn't named, no one goes to prison.
A classic story is someone being assigned to a classified military project and later reading about all the details in an issue of Aviation Week.
I have not read (nor will I read*) the published cables, but some of the "headlines" from them seemed to be "well duh" to anyone who spends a few minutes reading about regional history on Wikipedia.
*I am obligated to protect information I know is classified.
As I understand it, his claims in court are that he will be extradited from Sweden for things which are not crimes in the UK. If the US and Sweden admitted that ahead of time, then the UK might well not extradite him to Sweden.
Thinking about this some more, it does seem rather odd to me that the US doesn't just try to extradite Mr Assange from Britain, seeing as the UK seems quite happy to extradite their own citizens to the USA for activities that were not crimes inside the UK... This is a defence I've seen written by a Swede which does seem valid on the face of it.
I don't think the US is actually going to extradite him from Sweden nor does the DoJ really want to try him in an Espionage Case. If the US Government should win the case (and the appeals), it sets a precedent that reporters/journalist/etc can be arrested and tried for publishing interesting information that the government (or parts there of) would rather not be in the open. It setups up a power struggle and removes the ability of Military Members/Bureaucrats/Congressional Staffers/Representatives/Senators/Presidents to leak classified information anonymously (or not) and allow the press to publish the story (with or without their names). It creates a real legal minefield for political bosses, who may not be that bright.
From a real politik perspective better to have the man ruined and sitting in a Swedish prison for sexual assault for a few years (and terrified of men in black suits/pajamas) than attempt to have an Espionage Trial in Virginia.
Sadly, the operational fallout from Wikileaks is that it is harder for US Government Agencies to share information they have collected. In the wake of 9/11 attacks, there was a lot of work done to lower the barriers between compartmentalized information. In the wake of Wikileaks that was reversed. I wish I could find the article that talked about that being one of Assange's goals. This means that if the CIA has good operational intelligence about X and the FBI is investigating Y (which is related to X), they may not figure out that they are connected until Z happens