Lebanon's Constitution, promulgated in 1943, vests legislative powers in a unicameral legislature, the Majlis al-Nuwab or National Assembly, whose members are elected to four-year terms. The Constitution also mandates an executive branch and an independent judiciary. The president of the republic and a prime minister head the executive branch and collaborate to form a government. Members of the National Assembly elect the president for a single six-year term. The president, in consultation with the speaker and members of the assembly, appoints a prime minister and a cabinet who are responsible to the Assembly. An unwritten agreement, reached in 1943, provides the formula for power sharing between the Muslim and Christian communities. The president is always a Maronite Christian, the prime minister a Sunni Muslim, and the speaker of the assembly a Shia Muslim. Cabinet portfolios are allocated proportionate to the different religious groups' representation in the National Assembly. Political parties in Lebanon are identified with particular religious affiliations, and attempts to form national parties have generally failed.
Constitutional reforms enacted in 1990 granted greater political power to Lebanon's Muslim majority. The 128-seat assembly and cabinet portfolios are now equally divided among Muslims and Christians. Moreover, the powers of the president have been significantly reduced in favor of the cabinet and prime minister, who serves as the head of the government. The new constitutional division of power among the president, prime minister, and parliamentary speaker is seen as creating a semi-official ruling "troika."
These reforms follow several years of civil strife that erupted in the 1970s. The conflict was caused by the problems created by a large Palestinian refugee presence in the country and the emergence of a Muslim majority demanding a greater voice in the constitutional order. From 1975 to 1990, a civil war wracked the country, pitting Lebanon's Muslims and their Palestinian allies against the Christians. During this period, the country endured foreign military interventions and disruption of normal governance as rival militias, representing religious factions, battled for control. A Syrian-dominated Arab Deterrent Force arrived in 1976, but failed to impose a lasting settlement.
In 1982, an Israeli invasion forced Palestinian guerrillas from their strongholds in Lebanon. An incomplete withdrawal left a 15 km (9 mi) strip of southern Lebanese territory under Israeli occupation. In September 1988, a divided assembly failed to choose a replacement for outgoing president Amin Gemayel. When his term expired, Gemayel appointed the Maronite army commander, General Michel Aoun, to head an interim military government. Claiming this government violated the 1943 agreement, Muslim Prime Minister Selim al-Hoss, declared his government the only legitimate authority. In March 1989, Lebanese troops loyal to Aoun clashed with Syrian forces. Urgent mediation efforts by Arab countries followed. A "charter of national reconciliation" was proposed to end the civil war. Members of the assembly then met in Taif, Saudi Arabia, to approve this charter. The Taif agreement called for constitutional changes, the disbanding of militias, and reconstituting the factionalized Lebanese army into a unified force capable of maintaining internal security. In November 1989, the assembly ratified this agreement and elected a new Maronite president, Reni Mouwad. Aoun, who opposed the agreement because it did not stipulate the withdrawal of Syrian forces from Lebanon, declared himself president. Mouwad was soon assassinated and the assembly elected Elias Hrawi as his successor. The Taif accords opened deep fissures in Christian ranks. Violence between the Aoun-led "rejectionists" and "accommodationists" eventually resulted in Aoun's defeat in 1990 by joint Syrian-Lebanese military action.
Lebanon's return to relative normalcy is credited to the Taif accord. Most militias have been disbanded and the Lebanese army has successfully reasserted the government's authority. The improved political and security climate has buoyed investor confidence. However, the Syrian-dominated order has not yet consolidated support among the Maronite community, which remains uneasy with its diminished political power and Syria's role in Lebanon.
The first legislative elections in 20 years were held in 1992. Rafik Hariri was appointed prime minister. In 1995, Hariri resigned after a dispute with assembly speaker, Nabih Berri, over a constitutional amendment allowing President Hrawi to serve a second term. A Syrian-backed compromise cleared the way for Hariri's reappointment as prime minister and passage of a constitutional amendment extending Hrawi's term for three years. On 15 October 1998, the National Assembly unanimously elected Emile Lahoud to succeed Hrawi as president.