My complaint is not about the new guy. He is the second coming of Petraeus from what I’ve read.
My complaint is with Gates.
Again, Yon doesn't share that complaint.
The fact that Gates replaced McKiernan with an excellent officer -- possibly one who is better qualified for this particular job than the man he's replacing -- strongly suggests that Gates' motivation is something other than "wanting to be loved." And it certainly doesn't justify your saying that "all is lost."
As to the nature of this firing, there's almost certainly a deeper game afoot; possibly it's not a very intelligent game (most likely is not intelligent, if it originated from Obama himself). Or it might be a very useful move, designed to send a specific message. We'll see.