As the recent military clash between India and Pakistan stunned the world with its intensity, investors were fixated on another aspect of the conflict: the display of cutting-edge military technology.

Over the past month, two indexes that track the biggest defense stocks in China — a key military partner of Pakistan — and India surged by more than $36 billion in combined value, thrusting a long-overlooked sector into the spotlight. While China and India have both invested heavily to modernize their military, the latest confrontation offered investors a rare look into their real combat capabilities.