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 The international peacekeeping force was withdrawn from Lebanon in 1984.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. Libya bombing Relations between Libya and the United States under President Reagan were continually contentious, beginning with the Gulf of Sidra incident in 1981; by 1982, Libyan leader Muammar Gaddafi was considered by the CIA to be, along with USSR leader Leonid Brezhnev and Cuban leader Fidel Castro, part of a group known as the "unholy trinity" and was also labeled as "our international public enemy number one" by a CIA official. These tensions were later revived in early April 1986, when a bomb exploded in a West Berlin discothèque, resulting in the injury of 63 American military personnel and death of one serviceman. Stating that there was "irrefutable proof" that Libya had directed the "terrorist bombing," Reagan authorized the use of force against the country. In the late evening of April 15, 1986, the United States launched a series of airstrikes on ground