I want to think they were all statistics professors.

A statistic professor plans to travel to a conference by plane. When he passes the security check, they discover a bomb in his carry-on-baggage. Of course, he is hauled off immediately for interrogation.

"I don't understand it!" the interrogating officer exclaims. "You're an accomplished professional, a caring family man, a pillar of your parish - and now you want to destroy that all by blowing up an airplane!"

"Sorry", the professor interrupts him. "I had never intended to blow up the plane."

"So, for what reason else did you try to bring a bomb on board?!"

"Let me explain. Statistics shows that the probability of a bomb being on an airplane is 1/1000. That's quite high if you think about it - so high that I wouldn't have any peace of mind on a flight."

"And what does this have to do with you bringing a bomb on board of a plane?"

"You see, since the probability of one bomb being on my plane is 1/1000, the chance that there are two bombs is 1/1000000. If I already bring one, the chance of another bomb being around is actually 1/1000000, and I am much safer..."

But they probably weren't. Reading the article made me think of the people I see in security lines taking off piles of jewelry and rummaging around in their bag for their liquids or taking off elaborate footware. It always makes me wonder what they were thinking when they were getting ready to come to the airport, and the answer is they weren't thinking. I assume the same is true here. They didn't think "yes, taking my gun is a good idea," they simply didn't think about it at all. And that's what scares me. Think how many people we must pass every day that have a loaded gun in their pocket, people who think it's as natural as having their car keys.