Some former senior NSA officials wrote an open letter to President Obama. It's a very interesting read.
The sadder reality, Mr. President, is that NSA itself had enough information to prevent 9/11, but chose to sit on it rather than share it with the FBI or CIA. We know; we were there. We were witness to the many bureaucratic indignities that made NSA at least as culpable for pre-9/11 failures as are other U.S. intelligence agencies.
We prepared this Memorandum in an effort to ensure that you have a fuller picture as you grapple with what to do about NSA. What follows is just the tip of an iceberg of essential background information – much of it hidden until now – that goes to the core of serious issues now front and center.
What took them so long?