If he had just leaked the footage from the helicopter, and leaked it to congress or reputable news media, and done it non-anonymously, I could buy that he thought he was a whistleblower. I still think some level of punishment would be appropriate (clearly being discharged from the military and clearance permanently barred, and probably a less than honorable discharge, and probation at least). I still wouldn't have done it (if I saw something while working that I thought was a problem, I'd bring it up through chain of command -- there are plenty of legal ways within the military to challenge something, if you're willing to put in the effort).

Wholesale leaking of TS/SCI data, defined as being able to cause "exceptionally grave damage to national security", pretty clearly meets the definition of treason. I don't think a firing squad (actually, lethal injection) would be the best punishment, but life in prison certainly would be an option.

I can't wait for the AFN commercials about this incident!