It goes back to v important 1996 Khobar bombing incident. Considerable evidence pointed to Osama bin Laden and Al Qaeda (who were not nearly as well known then as now).
deseretnews.com/article/833096…



Drumroll..... none other than James Comey.
en.wikipedia.org/wiki/Khobar_To…

newyorker.com/magazine/2001/…
justice.gov/usao-edva/file…

reuters.com/article/us-sau…

cnn.com/2003/ALLPOLITI…

ipsnews.net/2009/06/exclus…
ipsnews.net/2009/06/exclus…
ipsnews.net/2009/06/exclus…
ipsnews.net/2009/06/exclus…
ipsnews.net/2009/06/exclus…