Can a man who tried to murder a president be rehabilitated?At 2:30 on Saturday afternoon, September 10, a hired SUV pulled up to the curb of a low-slung brick-and-wood house in suburban Virginia and let a passenger out. The man, who wore a tan baseball cap and a black T-shirt, did not glance at the paparazzi lenses trained on him but walked straight inside. He is far older now than in the notorious photos, but in many ways John Hinckley looks the same: blond, pudgy, nondescript. On June 21, 1982, a jury found Hinckley not guilty by reason of insanity...