 Complete the following phrase:  A civil war had broken out in Lebanon in 1975, and both Israel and Syria undertook military action within Lebanon in 1982. After Israel invaded Southern Lebanon, Reagan faced domestic and international pressure to oppose the Israeli invasion, but Reagan was reluctant to openly break Israel. Reagan sympathized with Israelis desire to defeat PLO forces that had struck Israel from Lebanon, but he pressured Israel to end its invasion as casualties mounted and Israeli forces approached the Lebanese capital of Beirut. American diplomat Philip Habib arranged a cease-fire in which Israel, Syria, and the PLO, all agreed to evacuate their forces from Lebanon. As Israel delayed a full withdrawal and violence continued in Lebanon, Reagan arranged for a multinational force, including U.S. Marines, to serve as peacekeepers in Lebanon. In October 1983, 