A newly announced billboard campaign is raising concerns that the Hungarian prime minister, Viktor Orbán, is once again using antisemitic tropes to further his political goals at home. For years, the Hungarian leader promoted the idea that shadowy global forces were conspiring to meddle in Hungary’s politics, prompting criticism that he was using antisemitic narratives to distract from the country’s challenges. In 2019, a controversial Hungarian government-funded campaign took aim at the Hungarian-American businessman George Soros and then-European commission president, Jean-Claude Juncker, prompting the commission to accuse Budapest of promoting a conspiracy theory. Now, Orbán appears to be returning to...