Hey bunch of genius!!! think what can be more damageable for the industry,...one late flight or another sept 11 massacre!!
Warning, a politically incorrect view follows.
After the great success of 9/11, the low tech approach (Madrid) has worked very well for them. Which is why central London got done.
I have said since 9/11 that flying continues to be the safest way to travel - for many reasons. One of them is that, they will not use aircraft in flight again. Of course, there may be some wild cards who will try their luck but, I doubt it.
Whilst shipping containers are good at getting materials into a country, they need to ensure that the bombs go off in the right place at the right time and that means having someone local to push the button. Trains and busses can never be controlled in the way that a/c ear, so they will continue to use them.
This is not a reason to stop security on all flights but the way in which the USA is turning flights away has no effect on insurgents and terrorists in any way what so ever. Except to provide them with a good laugh.
If they kept on using a/c they would not demonstrate their complete control but by varying the approach and the targets, they show us that they can do as they want. Which, of course, they can and will continue to do so untill we stop telling them how to lead their lives. Which will not happen anytime soon.