How could the guy either forget that the gun was in his bag or feel that he could get away with it? At some airports, we can all bypass security-you sit in a two-hour class and watch a video to earn the SIDA ID badge!!. But only at your homebase airport. DID an ex- or soon-to-be-EX-WIFE put it in after his bag was packed? Years ago, a Continental pilot's 'angry' wife put a 'controlled substance' into his food. She then called the airline, trying to get him fired. Of course he failed the urinalysis, either the gas-chromatography or spectrometer, or both. They gave him his job back very soon: somehow, the demented b---h confessed, or the airline probed and figured it out.
Believe me, these things have happened, and much more than once (If someone slipped drugs into your bag before you went to some Pacific Rim dictatorship nations, they will hang you, no matter who was responsible).
IF this was not the case, then this guy was very stupid and ignorant. Why do people who do the really stupid things actually believe that their employers need their services? Any of us can be replaced by reserve pilots or those who need extra money. Why is this a new concept for pilots, no matter how expensive their sim. training?? We are NOT critically-needed management officers.
Do we still carry "postal inspectors" in the US now, as in the old days, who can have a weapon with them? I would have to ask Dispatch or find clear language in the FOM to allow this.