Israel invades Lebanon to eliminate the PLO and get a free hand in the West Bank and Gaza Strip. Despite strong resistance over 75 days, the PLO loses the military front it built in South Lebanon and its political–military base in Beirut; the massacre in the Sabra and Shatila refugee camps takes place after the evacuation of the PLO fighters. Factional fighting and internal divisions mire its ranks from 1983 to 1987. The Palestinian leadership’s overtures for a negotiated settlement of the Palestine question are rejected by the United States and Israel.