Prior to going to Vietnam, I went to SERE training, which had a POW phase including a fenced compound manned by "enemy" guards. We were subjected to various forms of "torture" and physical abuse that caused some people to break in this simulated exercise. The one element that affected people the most was being put into a closed footlocker sized box in the sun for several hours. Those who had a fear of being in small, enclosed spaces (claustrophobia) broke and signed false confessions and read them over a loudspeaker to the prisoners below. A surreal experience.
Any man can be broken. Given McCain's serious injuries, torture, solitary confinement for three years, etc., I won't blame him for his forced recorded statements. No one knows how he or she would react under similar circumstances. McCain was no traitor to his country. He flew 23 combat missions over Vietnam. What have you done for God and country?