Key points:
- Spy balloons can linger over a site for much longer
- Spy sattelites have many threats against them. Not only kinetic threats that can destroy them, but chemical, directed energy, microwave and even optical countermeasures, the latter being widely employed.
- The US Space Force has admitted to dealing with devices which interfered with US Sattelites
- Space has essentially been weaponised for years
- New age of Spy balloons may be here due to advanced nations wielding countermeasures which block optical espionage by Spy sattelites, making Spy balloons much better bang for buck
- Photophoresis could be used in the future to deploy minuscule espionage devices across the world. These would be practically impossible to detect
- Widespread use of spy sattelites could cause Kessler syndrome in the event of a war making low-earth orbit difficult.