I'd assumed much better bandwidth is available for the a certain class of satellite (gbits a second via laser to downlink) [1], but for cost effective surveillance high altitude drones [2] would be the tool of choice to monitor cities, if not the world.

[1] https://www.wired.com/story/how-to-build-a-space-communicati...

[2] https://www.theverge.com/2013/2/1/3940898/darpa-gigapixel-dr...