While I do think it would have been better if the US government didn't do the things it did, and released a statement on them sooner, what Manning did could have jeopardized the security of many people, especially if the information contained material to really piss off insurgents. At times of war, although we're almost always at war, it may be necessary to hide information, and we don't have the rights to know absolutely everything that goes on in our government, because some classified information should stay classified.
tl;dr he knew what he was doing so he shouldn't expect to get out; however, it would be nice.