Secrets, lone wolves, and inept terrorists
There there is a cautionary lesson in the silence of Oscar Collazo and Booth's abettors. Sometimes investigators close the books too early on a case. They fail to discover all the threads in a plot because the perps maintain their silence or persist in their lies.
This is especially true when the culprits are driven by ideology rather than the greed of common criminals. The Rosenbergs, after all, kept silent even though that meant a date with the electric chair. Alger Hiss kept lying for a half century.
Peter Lance's research shows that the FBI and DOJ missed important links in the terror cell that carried out the 1993 WTC bombing. Some of those links reappeared in the investigation of 9/11.
It is never wise to underestimate the enemy. Most of the recent terror arrests in the US have been reassuring. The accused look fairly inept. On the other hand, Timothy McVeigh was an inept bomber who managed to build the OCK bomb and kill 68 people. Terrorists can ride the learning curve just like any one else.