The real culpability lies...
with the commanders who forced Manning into the situation.
The poor guy was acting out, and was clearly not fit for duty - particularly in a sensitive area. The response of his chain of command should have been to relief Manning of all duties and keep him from anything more dangerous than a kitten. These clowns failed in their basic duties of personnel security, and have not suffered because of it.
Manning was just the fall guy: the 35 year sentence was clearly over the top.
This also demonstrates what a complete tosser Obama is. He all these years to do something about Manning and did nothing. Just as with standing up for the Palestinians, he made a meaningless gesture after the election of his successor, who made lots of noise in opposition to Obama. So Obama can go back to the only thing that he does well - preening himself.