Secure flying
If one really wants to make international flying perfectly safe (at least safe from terrorists masquerading as passengers), it is in fact very simple and quite cheap:
* No carry-on or check-in luggage at all (all kinds of chemical,
bacteriological or radioactive materials could be hidden there, for
example it can be trivial to make a laptop burn up in flames mid-flight
and make in in non-detectable way).
* No personal items of clothes (clothes can be soaked in certain
chemicals to make them explosive).
* Secure passengers during the flight ( so that they can not
actually do any terrorist activity).
So, the optimal way of securing air transportation would be to have
people come in without any luggage at all, remove all items and clothing
at check-in, dress in uniform one-time paper clothing where one can not
hide anything, sedate them, feed them trough introspective inspection to
detect in-body foreign objects and check the chemistry of skin and hair,
pack them into the airplane on secured padded shelves, fly them to the
destination, reverse the sedative and give them a standard set of clothes
and essential personal items.
In addition to perfect security, this plan will also reduce the
overall cost of air travel by allowing to pack more people into an
airplane of the same size - the padded shelves can go from the bottom of
the airplane to the very top with minimal spacing (all passengers are
sedated - they will not walk around), no separate cargo hold will be
needed (no luggage) and no in-flight entertainment or food will be
required.
If the current security craze continues, we might reach this
perfection by 2020. Congratulations!
Note: All software by that time will be Web-based, so there will be no sense in taking your "personal" laptop with you.