Explained in plain English

Who owns the airspace?

A country's airspace generally extends 12 nautical miles (about 22 kilometres) from its coastline, aligning with its territorial waters. Beyond this is international airspace, where aircraft can fly freely, but still need to identify themselves if approaching national airspace. The drones in the story were flying near and entering Estonian and Latvian airspace, prompting a swift NATO response to protect sovereign territory.