The dilemma of Bradley Manning

What should Bradley Manning do? In times of war, when you see something wrong, soldiers leak information to press, or wikiLeaks. They do this because they see that their leaders who they would have reported the wrongs are involved. Soldiers who leak information to the outside world, do a lot for humanity, but then retire to a lonely life loathed by countrymen and treated as traitors. But Bradley Manning is treated unnecessarily harsh and I wonder why. Loath him all you want but to jail him may not be legal. How can you punish someone for doing something right?