In March 1978, Israeli troops occupied South Lebanon, except for Tyre and its surroundings. The UN Security Council, ‘gravely concerned at the deterioration of the situation in the Middle East,’ called upon Israel to withdraw its forces from Lebanon and created UNIFIL (United Nations Interim Force in Lebanon; UNSC Resolutions 425 and 426). Some 4,000 UNIFIL troops – two months later increased to 6,000 – were stationed in the south of Lebanon.
Paradoxically, Israel’s role in the conflict increased in the following years. To begin with, it withdrew its forces from Lebanon, but retained control of an area in the south, manned by the Christian militia of Saad Haddad, called the South Lebanon Army (SLA). In 1981, Israel bombed Beirut. A year later, in June 1982, Israel invaded the country again. The Israeli troops now went as far as Beirut, laid siege to the Lebanese capital, crushed the Palestinian forces, and forced the PLO’s departure, which left for Tunis.
Shortly afterward, Bashir Gemayel, the son of Phalange leader Pierre Gemayel, was elected president. However, he was assassinated before his installation. It was said that the murder was committed on the instigation of the Syrians, who were now siding with the Palestinians, as the Maronite militias had become too strong from their perspective. Immediately after Gemayel’s murder, Christian militias massacred an estimated two thousand unprotected civilians in the Palestinian refugee camps of Sabra and Shatila.
Meanwhile, in the south of the country, fighting increased between the Israeli troops and the Shia militias. The Lebanese Resistance Battalions (Amal, Arabic for hope and acronym for Afwaj al-Muqawama al-Lubnaniya, Battalions of the Lebanese resistance) was created in 1975 as the military branch of the Movement of the Disinherited, which Imam Musa al-Sadr founded. The other militia was Hezbollah (Party of God). Amal was backed by Syria, Hezbollah by Syria, and Iran. In 1983, heavy fighting took place between Druze and Maronites in the Chouf Mountains. Both sides committed massacres which amounted to sectarian cleansing. The Druze, helped by Amal, tried to take Beirut but were stopped by the Lebanese Army under General Michel Aoun’s command.