“...no matter the cost.”
There’s your problem. How high a cost? Morale boost to the enemies and a decrease for our servicemen? Leaked secrets? Leaderless forces?
Pres. Bush and Sec. Def. Gates weighed the benefits and risks and deemed that the cost/benefit ratio is insufficient to bring back Pace, much to their chagrin.
I’m sure Sec. Def. Rumsfeld would make the same choice.