[formerly_proven]

Geostationary orbit is ~36000 km above the surface. Optical surveillance satellites work at altitudes of 200-400 km and already need Hubble-like mirror sizes to achieve the needed resolution. A geostationary satellite with a similar resolution is simply not possible to build and launch in this age. Geostationary also means that half the time you're looking at darkness.

[krisoft]

Thank you very much for the answer. (both you and all the other people)

> A geostationary satellite with a similar resolution is simply not possible to build and launch in this age.

I think I will have to read up on that specifically more. I was aware how far GEO is, but I don't understand what makes the optics impossible. (Clearly it is as you say, all the sources agree with you.) Thank you!