Do you believe that our collective fear, as a nation, of a terrorist attack which employs a nuclear or biohazardous weapon is rational?

Do you believe that our collective fear, as a nation, of a terrorist attack which employs a nuclear or biohazardous weapon is rational? In your opinion is such an attack possible or probable? Our experience in recent years wherein anthrax was employed as a terrorist weapon via the U.S. Postal Service was a “wake up call.” Do you feel that we are now, collectively as a nation, dozing off again?