How do you shoot down a plane sized object at 4,000 miles even ASSUMING you have a beam weapon that can hold coherence through 4,000 miles of atmosphere...
AND... track the object while moving at 12,500 mph???
We might as well surrender now, and learn Mandarin. Because they can shoot down every plane or missile we can field.
The FROM WHERE question is a good one.
This is all really wild speculation based on questionable photos that none of us have seen, but . . .I fear that the technology is here or will be soon. How to deploy it successfully for this kind of attack would call for some sneaky thinking but even that is not hard to come by.