At 4,600 meters above sea level, snow seals this outpost for half the year. Oxygen is scarce, and comfort is absent. But young soldiers of the Xizang Shigatse Military Sub-command don't go there for an easy life. They go to serve. Recently, they patrolled a 5,000-meter route knee-deep in snow, with each breath a battle.

This is the choice of a generation with purpose.