Now that we are alert for terrorism in the air, the next terrorist act will not come from the sky but through biological or chemical weapons in a public place, for example at Times Square when the New Year's ball drops.
However, for the moment, let's focus on air travel. We've come to realize that no amount of airport security with respect to carry-on items will prevent a high jacking. Three strong men armed with ball point pens and shouting that they have shampoo bottles full of anthrax could be successful in a highjacking. In this respect, it is not useful to overly restrict the nature of items carried onto planes.
Instead, we should add a voice-activated system in the cockpit such that when the pilot says the word "Zanzibar," the plane can't be highjacked. The code word also triggers an emergency alert to air traffic controllers. The plane is sent into autopilot mode. Other biometric devices, such as fingerprint readers, might be useful.
If the cockpit is to be physically isolated, a video monitor must be installed in the cockpit so that the pilots can see the cabin and flight attendants to check for misdoings and also to avoid the feeling of extreme isolation that one might encounter when locked into a small compartment for many hours. Similarly, the flight attendants should have access to a monitor so that they can see the pilots during conversations, which would also reduce the feeling of imprisonment and isolation.
We should also put a toilet (or other waste collection system) in the cockpit so that the pilots need not leave the cockpit.
In all cases, it is sad that convenience and personal liberty will be sacrificed while prejudice is increased. Will four men named Mohamad ever be allowed on the same plane?