Hamas is a Palestinian Islamist political organization and militant group that has waged war on Israel since the group’s 1987 founding, most notably through suicide bombings and rocket attacks. It seeks to replace Israel with a Palestinian state. It also governs Gaza independently of the Palestinian Authority.
Hamas’s charter long called for the destruction of Israel. It was revised in 2017 to allow for acceptance of a Palestinian state in the West Bank and Gaza Strip rather than the entire territory, though Hamas still refuses to recognize the legitimacy of the Israeli state.
Hamas led the charge in using suicide bombings against Israel in the 1990s and 2000s, though in recent years it has shifted to rockets and mortars as its weapons of choice. The organization also offers Palestinians a robust network of social services, which it developed as an alternative to deeply corrupt PA institutions.
In 2006, Hamas won a slight majority of the seats in the Palestinian Authority legislative elections. This would have put Hamas in a commanding position for both the West Bank and Gaza, but there was a problem: Hamas refused to accept previous deals that the PA had made with Israel. That lead Western powers to freeze out aid, which the PA depends on, to any Hamas-led PA. Tensions between the PLO and Hamas eventually escalated to outright war between the two factions, which ended up with Hamas governing Gaza independently from the West Bank–based PLO.
Unity talks between Hamas and the PLO have broken down repeatedly, which means there is no unified Palestinian authority, complicating peace talks significantly. In late 2017, the two sides reached a preliminary unity agreement, but it’s still unclear whether this will lead to an actual united government of any kind.