Origin

(Hebrew: ארגון‎; shorthand for HaIrgun HaTzva'i HaLe'umi BeEretz Yisra'el, הארגון הצבאי הלאומי בארץ ישראל, "National Military Organization in the Land of Israel") was a militant Zionist group that operated in Palestine between 1931 and 1948. It was established as a militant offshoot of the earlier and larger Jewish paramilitary organization Haganah (Hebrew: "The Defense", ההגנה). For secrecy reasons, people often referred to the Irgun, during that time, as Haganah Bet (Hebrew: literally "Defense 'B' " or "Second Defense", הגנה ב), or alternatively as Haganah Ha'leumit (ההגנה הלאומית) or Ha'ma'amad (המעמד). In present-day Israel, Irgun is commonly referred to as Etzel (אצ"ל), an acronym of the Hebrew initials.

The Irgun was the armed expression of the nascent ideology of Revisionist Zionism founded by Ze'ev Jabotinsky. He expressed this ideology as "every Jew had the right to enter Palestine; only active retaliation would deter the Arabs and the British; only Jewish armed force would ensure the Jewish state". Initially, a central part of their efforts included attacks against Palestinian Arabs, but it increasingly shifted to attacks against the British. Some of the better-known attacks by Irgun were the bombing of the King David Hotel in Jerusalem on 22 July 1946 and the Deir Yassin massacre (accomplished together with the Stern Gang) on 9 April 1948. In the West, Irgun was described as a terrorist organization by The New York Times newspaper, and by the Anglo-American Committee of Enquiry. Irgun attacks prompted a formal declaration from the World Zionist Congress in 1946, which strongly condemned "the shedding of innocent blood as a means of political warfare".

Irgun was a political predecessor to Israel's right-wing Herut (or "Freedom") party, which led to today's Likud party. Likud has led or been part of most Israeli governments since 1977.