 In the 1940s the left-wing of Mapai broke away to form Mapam.Labor Zionism became the dominant tendency in the World Zionist Organization and in 1935 Ben-Gurion became chairman of the executive committee of the Jewish Agency, a role he kept until the creation of the state of Israel in 1948.During the 1936–1939 Arab revolt in Palestine, Ben-Gurion instigated a policy of restraint ("Havlagah") in which the Haganah and other Jewish groups did not retaliate for Arab attacks against Jewish civilians, concentrating only on self-defense.