-> ...why wouldn't a potential terrorist just wheel up a carry on sized bomb and detonate it in the middle of the "security" line? I have no idea. To me, by fa

-> ...why wouldn't a potential terrorist just wheel up a carry on sized bomb and detonate it in the middle of the "security" line? I have no idea. To me, by far the most dangerous part of flying is the queue at the TSA checkpoints, especially at airports with particularly large checkpoints (I'm thinking EWR and probably ORD). I think some airports address this (SEA, MSP, JFK...maybe) by spreading out the checkpoints among smaller groups of gates to keep the volume of people at those checkpoints down. This is just my speculation, however. I'd be curious to see how checkpoints have evolved over the last 14 years in terms of design and efficiency.