The exploitation of the accusation of antisemitism, especially to delegitimize criticism of Israel or opposition to Zionism, is sometimes called weaponization of antisemitism. Cases of weaponizing antisemitism have arisen in various contexts, especially regarding the Israeli–Palestinian conflict. There has been controversy over the concept of new antisemitism and the IHRA definition of antisemitism, both of which characterize criticism of Israel and opposition to Zionism as antisemitic. Charges of antisemitism made in bad faith have been described as a smear tactic and likened to "playing the race card". Some anti-Zionist Jews have been accused of antisemitism and labeled "self-hating Jews".

The charge of weaponization has itself been criticized as antisemitic or rooted in antisemitic tropes, and as a rhetorical device employed across the political spectrum to delegitimize concerns about antisemitism, especially in anti-Zionist discourse. These controversies have intensified during the Gaza war.

In 1943, when a British court heard a case about Jews engaged in smuggling weapons into Palestine, future Israeli prime minister David Ben-Gurion called the case "a crude frame-up designed to defame the Jewish people" and called the speech of the defence counsel, who sought leniency for the defendants on the ground that they had been ensnared by a gun-running ring, "characteristic of the lowest type of anti-Semitism". Christopher Sykes wrote in 1965 that this incident began "a new phase in Zionist propaganda" in which "to be anti-Zionist was to be anti-Semitic". Propaganda theorist Noam Chomsky has written that, although Sykes traced the origins of weaponized antisemitism to this episode, it was not until "the post-1967 period that the tactic has been honed to a high art, increasingly so, as the policies defended became less and less defensible".

According to historian Ilan Pappé, after the 1967 Arab–Israeli War, the Anti-Defamation League (ADL)—with AIPAC founder Isaiah L. Kenen's support—sought to "portray certain 'anti-Israel' actions as anti-Semitic", especially with regard to international calls for Israel to end its occupation of the West Bank. In 1974, ADL leaders Arnold Forster and Benjamin Epstein published The New Anti-Semitism, which identified anti-Zionism as a "new antisemitism", an idea the ADL has sought to popularize since the early 1970s.

In 1973, after the Yom Kippur War, Israeli foreign minister Abba Eban wrote: "One of the chief tasks of any dialogue with the Gentile world is to prove that the distinction between anti-Semitism and anti-Zionism is not a distinction at all. Anti-Zionism is merely the new anti-Semitism." Of Eban's statement, Chomsky later said: "That is a convenient stand. It cuts off a mere 100 percent of critical comment!"

In 1980, Edward Said said that, since its inception, Zionist discourse had aimed "to lay claim to Palestine both as a backward, largely uninhabited territory" and as a place where Jews had "a unique historical privilege" to rebuild a homeland. As a result, he said, this meant anyone who opposed Zionism "immediately aligned oneself with anti-Semitism". Said said this routine conflation of anti-Zionism with antisemitism functioned to suppress criticism of Israel and was reinforced by simplistic media narratives, the influence of pro-Israel pressure groups, and academics' and intellectuals' uncritical repetition of political clichés.

In 1952, a "confession" was extracted under torture from Rudolf Slánský, former general secretary of the Communist Party of Czechoslovakia, of "shield[ing] Zionism" by accusing its critics of antisemitism. David Hirsh describes this as a deployment of the Livingstone Formulation characteristic of Soviet antisemitism.^{[page needed]}

Sociologist Anna Zawadzka has argued that the Livingstone Formulation was already in use in Poland in 1968, such that Jews "could not articulate their experiences of antisemitism" without having their articulations "diagnosed as either cynical victim-playing or an emotional disorder." She interpreted this response as a form of "paternalistic violence", viewing the traumatized Polish Jews as deserving of sympathy, but not of trust in their view of antisemitism in the decades following the Holocaust. Zawadzka wrote that this paternalistic view has changed, with Jews now being taken as cynical and manipulative rather than as traumatized and paranoid in their articulations of antisemitism.