I say, give him a trial--in India.
The focus on whether he did or would shoot at an American should not be the crucial issue. He admitted that he fought with Al-Qaeda in Afstan and Kashmir. Did he help kill Afghan ethnic minorities? He admitted fighting or abetting terrorism in Kashmir. Get him to confess more. Then "decide" that he has to be transfered to India for his crimes there. Let the Indians have him and try him. This will be the best lesson to teach. Teach America about the world and "consequences." Don't let him come back to America for a media sympathy-fest where consequences for one's actions are suborned in favor of media driven emoting.
This insight bears repeating.
I agree with you. His parents will milk this and have John Walker tried via media before he goes to any trial, IMHO.