Garett’s main point – air travel terrorism has enormous social costs counting the effect on foreign policy – is clearly correct.  The straightforward implication: Mildly reducing the risk of terrorism with major inconvenience for air travelers easily passes a cost/benefit test.

However, none of this argues in favor of mere security theater – like making sure people’s tickets match their I.D.  In fact, Garett’s point is an powerful argument against security theater.  First, security theater is a waste of resources that could be reallocated to actually reducing the risk of terrorism.  Second, and more importantly, security theater probably increases public resentment against all airport security. 

Closing question: I’d be curious how far Garett would take his argument.  Couldn’t terrorist attacks on trains, malls, sporting events, or bridges also have massively bad effects on foreign policy?  How expansive and pervasive would a global utilitarian’s security measures be?