Ronald Bailey writes for Reason:
[Y]our risk of dying in a plausible terrorist attack is much lower than your risk of dying in a car accident, by walking across the street, by drowning, in a fire, by falling, or by being murdered.
Already, security measures—pervasive ID checkpoints, metal detectors, and phalanxes of security guards—increasingly clot the pathways of our public lives. It's easy to overreact when an atrocity takes place—to heed those who promise safety if only we will give the authorities the "tools" they want by surrendering to them some of our liberty. As President Franklin Roosevelt in his first inaugural speech said, "The only thing we have to fear is fear itself— nameless, unreasoning, unjustified terror which paralyzes needed efforts to convert retreat into advance." However, with risks this low there is no reason for us not to continue to live our lives as though terrorism doesn't matter—because it doesn't really matter. We ultimately vanquish terrorism when we refuse to be terrorized.
See also this paper by John Mueller of Ohio State University: A False Sense Of Insecurity? [PDF]
