2.1 Definition of Air Space

The air space = the space above the land-and-water territory of the state — the state's territorial column: the airspace above the national territory (the land, the internal waters, the territorial sea) and, in law's classic phrasing, the subjacent airspace of the state's domain. The vertical extent's question (the definitional debate): how high does the column run? — the theories: the atmospheric definitions (the air's reach — the breathable-and-navigable air as the airspace); the effective-control theory (the altitude of actual control — the sovereignty as far as the state can enforce); and the modern settlement's edge: the airspace ends where the outer space begins — the delimitation problem (the Karman-line candidates vs. the functional approach — Unit 7.2's full debate; the airspace law presupposes the column without fixing its ceiling in a treaty text).