Central to Walt and Mearsheimer's hate-filled screed against Jewish participation in American politics was their assertion that it is perilous to speak out against Israel. Anyone who does so, wrote the authors, faces squashing at the hands of the "Israel Lobby," a shady conglomeration of lobbyists, journalists, philanthropists, academics, and public servants. "The core of the Lobby is comprised of American Jews who make a significant effort in their...