Karel De Gucht, the European trade commissioner, has a penchant for saying what he’s really thinking. As Belgian foreign minister, he ruffled feathers across the globe. He was notoriously tough on Belgium’s former colony, the Congo, criticizing corruption and emphasizing that Belgium’s aid contributions gave it “the moral authority to comment on issues affecting the country.” Congo subsequently banned Mr. De Gucht from visiting.On Thursday, with the Middle East peace process in the news, Mr. De Gucht picked yet another fight. Jews, he told Belgian radio, have a “belief” that they are “always right.” He described his frustration at debating the Middle East because “it is not easy even with a moderate Jew to have a conversation”...