When's the last time a fact-finding commission actually found a useful fact? There's always plenty of fault-finding, and sometimes facts emerge from all the "he said-she said-they said-we said" testimony. But what about facts that might actually help to prevent a future disaster?
I can recall only Richard Feynman's discovery of O-ring failure as the cause of the Challenger disaster in 1986. But finding that fact didn't prevent the loss of Columbia 17 years later.
Finding useful facts becomes even more problematic in the exponentially more complex world of human behavior. Our understanding, such as it was, of the causes of Pearl Harbor didn't prevent 9/11. Our understanding of 9/11 will not prevent future terrorist attacks within the U.S.
But the headline writers and pundits are having a field day, so the game must go on.