I've long heard accusations that Mossad withheld advance knowledge about 9/11. But while it's okay to accuse the CIA, God forbid anyone accuse Mossad of the same thing.
We don’t know FACTs in either situation — 9-11 or Gaza. All so far, in both events, are just opinions/rumors/hearsay etc, and NO FACTs have emerged in either case. I truly wish we could find out, but it’s all been probably “sanitized”.