PANGONG TSO—Eighty-two-year-old Tseten Namgyal is dressed in an Indian army jersey. Age and the tough, intensely cold trans-Himalayan terrain has hunched his back a bit, and his visibly thick-skinned fingers look almost mummified yet alive. But his candor about being a 1962 prisoner of war and the servant and the porter of one of India’s most celebrated army officers is youthful and infectious. Namgyal was serving Major Dhan Singh Thapa when the 1962 war between India and China broke out. Then a post commander, Thapa’s valor during the war is a part of military history—he was awarded Param Vir Chakra, India’s highest military decoration for his valor during the war. Namgyal was a witness to that legendary fight.  He saw ten Indian soldiers succumb to the Chinese artillery, and he and nine others, including Thapa, were arrested and taken to Xinjiang as prisoners of war. He was the only civilian …