Re: Some background... and a little commentary
I'll add a little bit of insight when it comes to CLASSIFIED INFORMATION, and the cost of its disclosure.
First of all, the reasoning for classification is generally made by those who are trying to protect someone or something, including the government itself, from the results of disclosing that information. In general, release of such information would either endanger a person, endanger or embarass a nation, or create significant material loss. Or some combination thereof.
'For Official Use Only' is the lowest classifiication I'm aware of. In genderal, it's info that might be embarassing or would give an enemy an advantage in war.
'Confidential' is generally information that compromises something (like a tactical advantage in war) if it gets out, such as the design of a warship, or ongoing diplomacy. If it's released, it puts significant advantage into the hands of enemies.
"Secret" is (as far as I can tell) information that could GET SOMEONE KILLED it if got into the wrong hands. Example, the location of a submarine, or the identity of a spy.
"Top Secret" would be, I assume, much like 'secret' except "more so", perhaps large numbers of people would be in danger of being killed. Military operations, details about embassies, defense plans, etc. might fall into this designation.
And I think there are higher ones, too. In short, these secrets exist for a REASON, and they should be KEPT secret. Or, pay a SEVERE penalty for their disclosure.
Pvt Manning was apparently privy to this kind of information, or had access to it, and then BROKE TRUST by DISCLOSING it. Without any knowledge of the ripple effects, it was given to Wikileaks to be publically disclosed. Although there was at least SOME information there (about spying on citizens, as I recall) that SHOULD have been "whistle blown", THIS was not the way to do it. And so Pvt Manning went to prison for it.
However, Wikileaks itself SHOULD NOT be held criminally liable for publishing the disclosed information, particularly because Julian Assange isn't a U.S. Citizen. I expect the investigation is to prove whether or not Wikileaks was involved in any illegal activity that led to its publishing, like cracking into a computer or similar. There are similar legal precedents in the USA regarding "the press" so long as they're not doing any illegal things to GET the information. if someone simply tells them, hands over a document, etc., that is NOT illegal. Cracking a computer to get it, on the other hand, IS. But the investigation into Wikileaks is probably just another "witch hunt" just like the Muller probe on Trump, which concluded with "no collusion", rightfully so. I expect a similar conclusion of "nothing illegal done" for WIkileaks.