I agree completely, I didn't intend to argue that this particular plane or one like it is necessary (especially as I haven't managed to read the linked article

I agree completely, I didn't intend to argue that this particular plane or one like it is necessary (especially as I haven't managed to read the linked article yet!), but that satellites alone are not sufficient and some form of atmospheric craft still has value at the moment. Interestingly they were already experimenting with drones back when they were flying the Blackbird - I wonder how good they are now?