US intelligence officials learned more about Abdulmutallab’s links to al-Qaida during his flight to Detroit, and intended on questioning him when he landed.
According to law enforcement, had the information been compiled sooner, he could have been prevented from boarding in Amsterdam. According to an administration official however, the information would not have motivated further scrutiny.
This highlights the complexity of counterterrorism and border security systems: because of current protocol, foreign visitors face greater scrutiny upon arriving in the US than they do getting on planes in the first place. There is also a great deal of information about passengers that is only compiled shortly before flights, in a comprehensive list called a manifest. It was a review of the manifest that revealed red flags on Abdulmutallab.