Doors were locked during flight, but not "hardened" and therefore potentially easy to breach (which the plotters didnt accomplish but the pax on 77(?) did over PA). But the other answers are more to the point, they were able to take advantage of social engineering to use what were considered benign and acceptable tools as weapons to take control.

If memory serves well knives were not prohibited pre-9/11. So the regulatory failure was responsible for what happen. The same regulator now in charge of security, federal government.

ID requirements were added after the crash of TWA 800. A common belief is that the airlines had already wanted this to prevent ticket resales, and once they had the opportunity to blame the government for "making them" check IDs they were happy to take it.

There was no "smuggling" involved. The blades were permitted by regulation to be allowed to be taken onboard, they were not prohibited. They could have been openly dropped into a tray that went though a scanner and nothing would have happened. Unfortunately it is common in media articles to incorrectly/falsely state that the items were "smuggled" aboard, thus perpetuating the lie.

Sure there are other aspects that can be legitimately considered as contributing causes, such as non-hardened cockpit doors, a policy to cooperate with hijackers, etc., but a failure of airport security screening was NOT one of them.

Without pay I would expect fewer and fewer TSA screeners will be able to report for unpaid work so those flying may get the choice to fly without adequate security or not fly soon.

Yes, 1996. The ID check was not at the security checkpoint but at the check-in counter, where most passengers would exchange a paper ticket (the first e-tickets rolled out in 1994 or 1995, but the vast majority of tickets were still paper in 1996) for a paper boarding pass and need to show ID as part of that process.

That's the way it was pre-9/11 paranoia. Security policy and procedures were set by the FAA Office of Civil Aviation Security.

I would fly without TSA. What has been permitted for me to take aboard changes with each agent. What needs to be taken out and placed in the bin differs as well.

The nasty expensive nude a scope didn't eliminate pat downs.

Basically I felt just as safe travelling prior to TSA. I agree if must have, should not be federal employees. I think there would be more accounts for their actions.

Did you see--plans to privatize security were announced. https://onemileatatime.com/news/trum...t-funding-tsa/

It should be put back onto the airlines, they have the most vested interest in being secure AND cost effective.

Partnership between the airlines and the airports with airports being the lead authority. TSA should publish security standards and have inspection teams verifying compliance. Red Teams could surveil actual screener performance and compliance with published guidelines.

Perhaps take lessons from how the rest of the world does security?

how do they do it?

It starts with the fees the airport authority charges for origination and transit. They don't have to charge the same amount. For example, MUC and FRA charge different airport fees. So in essence they compete with each other. Here airports can charge $4.50, no more, no less.

In a perfect world, LGA, EWR and JFK could charge different amounts and compete with each other, service for price. MUC is more expensive to transit, but most flying LH would rather transfer there than the cheaper FRA. And in most of the world, the airport authorities run security much like in SFO, subject to government-imposed standards, and pay for it with the airport fees.

Comprehensive guide to European airport taxes and fees - Points with a Crew
(This is an old document, but you get the idea).

Even though LGA, EWR, JFK, SWF and TEB are all owned by the Port Authority of NY/NJ and TSA runs security at all of them, some of their individual terminals are operated independently and offer considerably different experiences. Vantage Group runs LGA Terminal B and JFK T7 and will run the forthcoming JFK T1 and T6. A company called JFKIAT runs JFK T4. The Munich Airport Group operates EWR Terminal A. Individual airlines run JFK T5 (B6) and T8 (AA), LGA Terminal C (DL), and EWR Terminal C (UA).

This can have an effect on the security experience. While TSA controls everything starting with the ID checkers, I believe the terminal operator decides how the queues that lead to the ID checkers are set up and how many of the active ID checkers at any given time are assigned to each queue (precheck, CLEAR, priority, general, etc.). A couple years ago I was at LGA Terminal C and was stuck in a nearly hour-long general queue (I was dropping off a UM, and gate passes for UM accompanying adults aren't eligible for precheck). I'm pretty sure that DL had purposely assigned only a single TSA ID checker to the general queue but had assigned two to the CLEAR queue so that CLEAR salespeople could pitch CLEAR signups to folks in the general queue who were desperate to catch their flights (I understand DL gets a commission from CLEAR signups that happen in "their" terminal). I thought that was particularly lousy.