By the way, you might be interested to know that recent reporting [0] (by
Rolling Stone contributing editor Seth Hettena on the Substack
SpyTalk, the media project run by veteran former Newsweek national security reporter Jeff Stein), based on legal filings in Guantanamo Bay cases against 9/11 plotters, suggests that the FBI believes the CIA
did fund some of the 9/11 terrorists, in the sense that they were cultivating them as intelligence sources. The mundane explanation is not that they sanctioned or even knew about the 9/11 plot, but rather that they failed to share intelligence with the rest of the intelligence community because they didn't want to compromise their source. But there is credible evidence to suggest that the terrorists were not only on the radar of the CIA, but were being actively developed as sources.
[0] https://www.spytalk.co/p/exclusive-fbi-agents-accuse-cia-of