No luck needed. Just common sense and experience.
Any organisation which has a history of targeting/threatening commercial aviation with terrorist acts. Islamic or otherwise.
A commercial pilot should not have any links to any organisation which has a history of threats to aviation. At the very least the pilot should be completely open to scrutiny.
You really sure you want to go with that one ?
Given your location how do you know that the guy you speak to every day on way into work and chat about English premiership is not a member of Al Qaeda.
Your conversations with him where you mention you support Arsenal and him Chelsea and you discuss previous weeks results goes on for months all the while he never mentions that a cousin was a hijacker United Flight 175 on 9/11. You kindly offer to bring him back some Chelsea stuff on next visit to London.
You bring it back and a week later get arrested for being part of a cell..........
Thats how easy it is for security services to assume you are part of it.
All fiction but unless you know the background of every single person you ever come in contact with you can never know.