"Going postal"
First, with all deference to the generally great employees of the USPS, I use this as a generic term to represent day traders etc. that go ballistic and start shooting coworkers and customers.
The question is, how long will it be, if ever, before one of the National Guard types develops a brain tumor or just a bad attitude, and starts shooting??? What precautions are being taken?
Do they really need those automatic weapons? Unless they're expecting an armed brigade storming Security, wouldn't pistols allow them to cope with most any contingency?
I sure hope that I'm worried about nothing, but this happens often enough in the outside world that I hope that somebody has at least considered the possibility in Airports.