I don't think many of us have been "blissfully secure" since 911. I know I haven't but life has to go on. I believe this is very probable but that they will also go back and try to take down whatever target the 4th plane was headed for.
I have been and still am. But, far more than the simple fact that I live in "flyover country," I give credit for my blissful security to the One in whom I believe. "If God is for us, who can be against us?"
Time marches on. Eternity awaits. No problem! :-)