I think I figured it out.
It seems all weird that they were able to roll out such pointless and irrelevant new security restrictions in such a short amount of time unless they already had these things in place and ready to go.
So it's pretty obvious. The TSA has a predetermined progression, a series of increasingly more restrictive steps, already in place. So whenever there's any kind of 'incident,' no matter how hamhanded or ridiculous, it triggers the next step. So, bit by bit, like the apocryphal frog in boiling water, we'll become acclimated to increasingly ridiculous restrictions, until airline passengers are strapped to boards wearing Hannibal Lecter masks and just stacked up like cordwood in the cabin for the duration of their flights.
MARK MY WORDS. MARK THEM!