Why is an unarmed young black woman who knocks on a stranger's front door to ask for help after her car breaks down perceived to be so threatening that he shoots her dead? Why do we fear infrequent acts of terrorism more far more common acts of violence? Why does a disease like Ebola, which killed only a handful of Americans, provoke panic, whereas the flu--which kills tens of thousands each year--is dismissed with a yawn? Jumping at Shadows...