John Brennan was CIA station head in Riyadh, no? And personally approved the visas of 15 of the 19 hijackers, did he not? And the FBI did nothing with the reports from flight schools, right?

I don't think there was a bomb in the South Tower or any demo charges. I think the two airplanes full of jet fuel were enough. But were there insiders who had a clue and wanted to let whatever was going to happen happen? Yeah, there were.