Maybe not sudden. How about the theory that he was upset about deployment because it would interfere with his (their?) plans for terror-attack on US soil?
He could have been a mole. MSM & WSJ portray him as a victem. We have an all volunteer military. Immediate Background Investigation required. Who are his associates and where did he associate. Jordanian background is the only thread offered in WSJ to his world view. No doubt he was conflicted.