While I feel sorry for Private Bradley Manning, the young man made a huge mistake for downloading classified information and giing it to Wikileaks. He made the biggest mistake of his young life.
First of all, when you enter the military and raise your right hand and take an oath to protect against foreign or domestic enemies and say, "I do," you are now committed to do just that. That oath is taken by all enlisted personnel and officers. In the olden days of George Washington, the punishment was death. The only person who can commute your sentence is the president of the United States.
If they decide to find him not guilty, they would give him a dishonorable discharge. Not too many employers want to hire that type of person. They may have some protected company patents. When i went to work in 1959, I had to sign a form not to give away any of the company products.