Political Bombshell: Rand Paul to attack classified Saudi link to 9-11 by every means possible.

[Babel_17]

131. My guess is that the incredbly large Saudi royal family has its finger in lots of pies

I don't think that can casually be explained but we're talking thousands of people with significant cash. Gaining influence/sympathy with diverse groups might be seen as the best thing for the royal family. And it might even go beyond that including plausible deniability for the top of the royal family. There could be competing factions, and/or no real agreement on what's best.
In exchange for favors from factions friendly to the US government/the then current administration, our government might have decided to sweep some stuff under the rug. Maybe they thought they were avoiding stirring up a hornets nest. By avoiding embarrassing revelations, they avoided compelling Saudi Arabia from cracking down on, and possibly further radicalizing, any dissident members of their wealthy elite (so they might have told themselves).
Just thinking out loud, not making excuses. I wasn't a fan of how all those post WTC attack hearings seemed to gloss over a lot of important areas worth exploration.