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 Israeli's 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, two nearly-simultaneous bombings in Beirut killed 241 American soldiers and 58 French soldiers. The international peacekeeping force was withdrawn from Lebanon in 1984. In reaction to the role Israel and the United States played in the Lebanese Civil War, a Shia militant group known as Hezbollah began to take American hostages, holding eight Americans by the middle of 1985. The Reagan administration's attempts to release these hostages would be a major component of the Iran-Contra Scandal. In response to the U.S. intervention in Lebanon, the Defense Department developed the "Powell Doctrine," which stated that the U.S. should intervene militarily as a last resort and should set clear and limited goals in such interventions. Though termed the Powell doctrine, the policy was originally developed by Secretary of Defense Weinberger, who was influenced not only by Lebanon but also by the experience of the Vietnam War.