hese days at the National Air and Space Museum in Washington, before visitors can see the Wright Brothers' 1903 Flier, Charles A. Lindbergh's Spirit of St. Louis, a touchable sample of lunar rock or any other souvenir of humanity's bounce toward the heavens, they first have to pass through a reminder of that morning the sky fell to earth. Advertisement The family-friendly museum now has visitors pass through a metal detector, open backpacks and diaper bags for inspection and, if need be, step aside for a brief pat down or a few waves of the beeping wand. The reaction of...