The other day, I experienced violent anti-Semitism for the first time in my adult life. It took place in front of Faneuil Hall, the birthplace of American independence and liberty. I was receiving a justice award from the Jewish Council on Public Affairs and delivering a talk on "Civil Liberties in the Age of Terrorism" from the podium of that historic hall. When I left, award in hand, I was accosted by a group of screaming, angry young men and women carrying virulently anti-Israel signs. The protest was denominated a peace event and was sponsored by a group calling themselves...