I just saw the Broadway play “Giant” in which Roald Dahl is portrayed as a principled supporter of Palestinians, who was driven to antisemitism by his support for human rights. The largely left-leaning New York audience, which was of course denied the true background of this horrible person, were led to assume that because he supported what is today’s major left-wing cause — namely Palestinianism — he must have done so out of principle and commitment to human rights. That is certainly the impression the playwright, actors and producers sought to convey. In that way they could present him as...