On October 11, four days after the Hamas-led attacks in Israel, President Joe Biden addressed a group of Jewish community leaders in the Indian Treaty Room of the Executive Office Building in Washington, D.C. “I’ve been doing this a long time,” Biden said. “I never really thought that I would see and have confirmed pictures of terrorists beheading children.” It was a jarring statement. And it was false. Biden had seen no such pictures, nor received any such confirmation. He made those comments after Nicole Zedeck, a journalist for Israel’s i24 News, reported that 40 babies had been decapitated, citing...