India, Jan. 15 -- The most lethal battlespace today is not high above the clouds, but the crowded airspace that determines whether soldiers can advance, hold ground, or survive.

Modern wars are still decided on land. Territory is seized, populations are controlled, and political outcomes are imposed by ground forces.

Yet the ability of armies to manoeuvre, sustain themselves, and fight is now determined less by control of the skies at high altitude and more by dominance of a narrow vertical band just above the battlefield.

This layer, commonly described in Western military literature as the air littoral, has emerged as the most contested and lethal battlespace of contemporary warfare.

The air littoral is not a new concept, but recent ...