A FRIEND OF MINE, an ex-radical who became a conservative and Deputy Sheriff of a Vermont town -- has a bumper sticker on his pickup truck that reads "Hanoi Jane Not Welcome Here." I admit to always having felt uncomfortable reading it, since it seemed to me to be an unnecessary reminder of the terrible, polarized atmosphere surrounding the war in Vietnam. It was a time when ultra-conservative supporters of the war showed their anger by what I thought was an unjustified demand that she be tried for "treason," because of what she had said in her trip to North...