HAMAS formed in late 1987 as a result of the first Palestinian Intifada (uprising). Its roots are in the Palestinian branch of the Muslim Brotherhood, and it is supported by a robust social and political structure inside the Palestinian territories. HAMAS has used various forms of violence, including high-profile terrorist attacks against Israeli civilian targets, designed to disrupt peace talks between Israeli and Palestinian officials and to prevent agreements aimed at ending the conflict. The group’s charter calls for establishing an Islamic Palestinian state in place of Israel and rejects all agreements made between the PLO and Israel. HAMAS’s strength is concentrated in the Gaza Strip and areas of the West Bank.

HAMAS has a paramilitary arm, the Izz al‑Din al-Qassam Brigades, which, beginning in the 1990s and up to the present, has conducted many anti-Israeli attacks in Israel and the Palestinian territories. These have included large-scale terrorist bombings against Israeli civilian targets, as well as small-arms attacks, improvised roadside explosives, and the launching of al-Qassam rockets into Israel. HAMAS continues to claim its right to confront Israel violently but has never deliberately attacked US targets. While the group receives some support from foreign countries and movements, it remains independent.

In early 2006 HAMAS won legislative elections in the Palestinian territories, ending the secular Fatah party’s hold on the Palestinian Authority and challenging Fatah’s leadership of the Palestinian national movement. Since then, HAMAS has largely refrained from suicide bombings or other attacks against Israeli targets but has refused to recognize the Jewish state explicitly or renounce violence. HAMAS militants violently took over the Gaza Strip in June 2007 and since then have worked to overcome international isolation by calling for a cease-fire with Israel, while demonstrating the group’s ability to provide security.