9/11 – Who Knew? Ask Senator Bob Graham:

I was surprised at the evidence that there were foreign governments involved in facilitating the activities of at least some of the terrorists in the United States.
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I think there is very compelling evidence that at least some of the terrorists were assisted not just in financing – although that was part of it – by a sovereign foreign government and that we have been derelict in our duty to track that down.
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It will become public at some point when it's turned over to the archives, but that's 20 or 30 years from now.