The disconcertment caused by the TSA allowing knives through the security lines highlights the futility of bureaucratic solution to an otherwise need for strategic risk management action. The long often exhausting lines at the airport gate simply give terrorists signals to strike elsewhere at the same time robbing citizens of the tranquility of travel. It validates terrorist success and perhaps an added incentive to strike again.
A cursory inspection of the anatomy of the 9-11 attack reveals that it was not that the attackers successfully carried box cutters through the lines; it was their ability to enter the cockpits and take over the plane from the pilot. Secured impenetrable armed cockpits would have prevented the cataclysmic event.
It was also the lack of vigilance that substantially contributed to the successful attack. There were ample red flag reports that foreigners were training to fly planes without any interest in landing them. A concerted effort to followup on this information and extract the plan would have foiled the attack. To make matters worse, or easier for the attackers, was the air security paradigm at that time to cooperate with hijackers and obediently follow their demands.
To repeat, the presence of TSA screening every person and their carry-on bag would not have prevented the determined 9-11 attackers; it was the lack of vigilance and vulnerable cockpit, pilots, and crew that made it all possible.
Vigilance of a US border inspector, not x-rays and metal detectors, is what caught the planned bombing of the Los Angeles International Airport by Ahmed Ressam, an Algerian al-Qaeda member. Review of the risk profile of the perils and hazards of air travel suggests that vigilance should be directed towards visiting non-citizens carrying within or without their person suspicious cargo that may disable an airplane and that their credentials invite further scrutiny. Citizens with all-American credentials should again enjoy hassle-free trips. Terrorists have not won.
Limited armed guards at the gate with a bomb-sniffing dogs plus gate inspectors armed with passenger manifesto and detailed search capability should suffice. Vigilant and proactive airplane crew and random air Marshall onboard are also requirements as they are the final line of defense.
TSA is a bureaucratic overreaction to a problem requiring a more effective and efficient solution. Give back the tranquility of air travel and keep it the safest way of getting from here to there.