Palestinians

Hamas, the Islamic Resistance Movement, surfaced in the West Bank and Gaza Strip with the outbreak of the first Intifada, or uprising against Israeli occupation, in late 1987. A Palestinian branch of the Muslim Brotherhood, Hamas is sworn to Israel’s destruction. Its military wing was at the vanguard of a suicide bombing campaign against Israel in the 1990s and during the second Intifada, which started in 2000. Its founder, Sheik Ahmed Yassin, was killed in an Israeli airstrike in 2004.

Hamas leaders, both local and in exile, refuse to recognize Israel’s right to exist and rule out a peace treaty with the Jewish state. At most, they have expressed readiness for a long-term truce in return for Israel’s withdrawal from areas that it won in the June 1967 war, notably East Jerusalem and the West Bank.

Hamas is seen as a terrorist organization by the United States, Israel, and much of the West.

Fatah joined Hamas in a Palestinian unity government in March 2007, the result of a power-sharing agreement brokered under Saudi auspices, but the partnership has been fraught with tension.

Fatah chafed at Hamas domination of the government and has refused to give up control of the official Palestinian Authority security forces. Hamas, for its part, was infuriated by the recent appointment of Muhammad Dahlan, a Fatah strongman in Gaza, as Mr. Abbas’s national security adviser. Mr. Dahlan, a former security chief, led a crackdown against Hamas in Gaza in 1996 which Hamas members recall for its cruel and humiliating treatment of prisoners.

Another source of contention was a multi-million dollar American-backed plan, funded by Congress, to bolster Mr. Abbas’s elite Presidential Guard, which is loyal to Fatah.

In June 2007, the rivalry broke out into the open with street fighting in Gaza that ended in a Hamas victory there. Mr. Abbas responded by dissolving the Hamas-led government and installing his own in the West Bank.

In December 2008, Israel responded to stepped-up rocket attacks on its border towns by Hamas by launching a large-scale air and ground assault into Gaza. The invasion, which left Gaza devastated, was criticized by Mr. Abbas, who nevertheless found himself losing popularity as Palestinians rallied to the side of Gaza -- and by extension, Hamas.

The United States and European Union train and support Mr. Abbas's troops in the hope of creating a strong enough force to prevent Hamas from challenging its West Bank rule and ultimately perhaps helping Mr. Abbas back into Gaza.

On May 31, 2009, six Palestinians were killed in the West Bank during a clash between Palestinian Authority forces and Hamas gunmen. Some 200 Hamas-affiliated men are in jail in the West Bank, but officials there insist they have been arrested for individual crimes, not for their link to the rival party. Hamas leaders in Gaza vowed retaliation for the shootings.

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