Isn't it easier to shoot them from the ground when they pass over? In space, the orbit must be adjusted to at least come close enough to the target, wait for the rendezvous, fire, then adjust orbit again for the next target...

I believe that attribution is more difficult in strictly on-orbit activities. I would imagine that these weaponized satellites use radar stealth approaches similar to modern fighter aircraft. AFAIK, ground radar is basically what we have for space awareness.

I would imagine that every new intelligence-related satellite will have more sensors to be situationally aware, and make attribution possible.

If you pay attention to space-nerd podcasts like MECO, "Space Domain Awareness" is getting a lot of investment. I believe that's because we are relatively blind at the moment.

https://en.wikipedia.org/wiki/Space_domain_awareness