We don't know the full story here. It could have been anything from a TSA employee with a vendetta, to an anonymous tip, to association with known bad guys at the mosque, or legitimate but classified intelligence information. In the case of that latter, they would not legally be able to let the guy have access to the information against him...he obviously doesn't have a security clearance.

Also, for your own clarification...

Flying airplanes has NEVER been a right, like driving but more so, it has always been categorized as a privilege. This means that the standards of proof and due process for pulling your tickets is low to zero, and almost any fed can do it for almost any reason. You cannot appeal to a real court with a jury of your peers, only to the NTSB, which almost always rubber stamps the FAA decision. A lawsuit in federal court would probably get rejected due to lack of jurisdiction.

In the case of TSA pulling your tickets, there is no outside appeal process that I am aware of. You can only appeal to the TSA itself.

IMO this might be OK for private pilots, but for professionals it is a bit Orwellian since your livelihood is on the line. I'm just elaborating for own enlightenment as to exactly where you (and the rest of us) stand on this.