It's always grimly funny to see how a TSA officer confiscates somebody's bottle of water, on the grounds that it might be a can of liquid explosive, and casually throws it to a bin full of other such water bottles, possibly full of liquid explosive, positioned right next to a large crowd of people in front of a TSA checkpoint.
That is, they are actively showing they themselves don't believe in what they are doing.
Seems like a perfect way for a terrorist to have a time bomb landed inside a 2L "soda bottle" in that confiscated bottles bin, and go board a plane, all clean.
TSA agents aren't serious people because the agency itself is not treated as serious - as many have pointed out in this thread, it was invented by people who were essentially larping as "serious people", staffed by more of the same, and then given a mandate that is, in fact, very serious.
If we treated TSA as serious we would deputize them as part of DoD, or as part of CBP and abolish the "checkpoint" version of this security theatre we're all complaining about. The Theatre doesn't make sense, we all know it, and as you point out the people working for TSA implicitly know it. A serious TSA agency would have armed troops, along with a myriad of other detection technologies, patrolling airports as is done in other major transportation hubs like Penn Station.
I've accidentally gotten pocket knives, lighters, actual ammo (shame on me, was coming from a military reunion where we spent time at a range) through security in my carry on. Once I was randomly pulled out and had the "sniff" test run on my bag (admittedly one that was in Afghanistan with me), where they wipe it down with a small piece of cotton and put it in a machine that does some magic I'm not smart enough to understand.
That is, they are actively showing they themselves don't believe in what they are doing.
Seems like a perfect way for a terrorist to have a time bomb landed inside a 2L "soda bottle" in that confiscated bottles bin, and go board a plane, all clean.