The problem is terrorism isn’t like car accidents.  In another thread somebody commented that more people die on the roads in a single day then died in the terrorist attacks in France.  Sure.  But the volatility in car accident statistics is tiny while the possible volatility in terrorist attacks is huge.  One well executed attack could kill hundreds of thousands or possibly millions if nuclear, chemical, or biological weapons are used.  Car accidents are a bell curve, while terrorism is the long tail.  And while I’m not really afraid of a terrorist attack, underestimating or dismissing a large group of people trying to actively kill you is naive.