Short answers, pulled from the story.
The first military aerial surveillance photographs were taken by American Army Corporal William Eddy during the Spanish-American War of 1898. Eddy adapted a kite-mounted camera design originally developed by British meteorologist Douglas Archibald in the 1880s.
In 1962, a U-2 reconnaissance aircraft captured images revealing nuclear missiles in Cuba, directly triggering the Cuban Missile Crisis. The U-2 flew at 70,000 feet to evade detection and used a Hycon 73B camera capable of resolving objects as small as 2.5 feet wide.
More than forty reconnaissance aircraft were shot down in European and Pacific theaters between 1945 and 1977. Of the 152 cryptologists who died during the Cold War, 64 were killed while participating in aerial reconnaissance missions.
The Compagnie d'Aeronautiers was the world's first air force, formed by France in 1794 to operate hydrogen-filled observation balloons. At the Battle of Fleurus that same year, its balloon L'Entreprenant remained airborne for nine hours, allowing French officers to observe Austrian Army movements.
Turkish Bayraktar TB2 military drones were used by Ukraine for both reconnaissance and strike missions. Civilian-donated hobby drones, including DJI Mavic mini models, were used by both Ukrainian and Russian forces for surveillance and targeting.
The FAA currently limits law enforcement drone operations to below 400 feet and requires operators to maintain visual contact with the aircraft. Operators must also hold specific licenses and certifications. The Department of Justice and Department of Homeland Security have each created additional policies to regulate domestic drone deployment.