At the time, PLO's objective was to establish a single democratic state in all of historical Palestine with equal rights for Jews, Muslims in Christians.

Fighting between the Palestinians and the Christian militias lasted until the Israeli invasion of Lebanon in 1982, which led to the expulsion of the Palestine Liberation Organization (PLO) from Lebanese territory.

While the PLO relocated to Tunisia in the aftermath of Israel's invasion, other Palestinian militant factions, such as the Syria-based PFLP–GC, continued to carry out low-level operations from Syrian-occupied Lebanon.

After 1982, the insurgency is considered to have faded in light of the inter-Lebanese Mountain War and the Israel–Hezbollah conflict, the latter of which took place for the duration of the Israeli occupation of South Lebanon.

[9] "The Palestinian resistance movement assumed daily management of the refugee camps, providing security as well as a wide variety of health, educational, and social services.

[14] The Popular Front for the Liberation of Palestine – General Command, which split from the PLO in 1974, carried out the Kiryat Shmona massacre in April of that year.

Changes in demographics and increased feelings of deprivation by certain ethnic groups, as well as Israeli–Palestinian clashes in the south of the country all contributed to the outbreak of the Lebanese Civil War.

Beginning in May 1976, Israel supplied the Maronite militias, including the Lebanese Forces, led by Bachir Gemayel, with arms, tanks, and military advisers.

Fearing loss of commercial access to the port of Beirut, in June 1976 Syria intervened in the civil war to support the Maronite-dominated government,[17] and by October had 40,000 troops stationed within Lebanon.

On 11 March 1978, eleven PLO militants made a sea landing in Haifa, Israel, where they hijacked a bus,[18] full of people, killing those on board in what is known as the Coastal Road massacre.

[18] On 22 April 1979, Samir Kuntar and three other members of the Palestine Liberation Front, a sometimes faction of the PLO, landed in Nahariya, Israel from Tyre, Lebanon by boat.

[21] The 1982 Lebanon war began on 6 June 1982,[22] when Israel invaded again in direct retaliation over the assassination attempt by ANO (Abu Nidal organization), a splinter group from Fatah) on Shlomo Argov, the Israeli ambassador to the UK, attacking Palestinian military bases and refugee camps affiliated with Palestine Liberation Organization and other Palestinian military movements, including the ANO.

[2] While the envisioned goal evolved, by 1977, PLO's political objective was to create a Palestinian state in the West Bank and Gaza Strip.

[25] The 1982 Israeli invasion in support of Lebanese Christian militias resulted in the Palestine Liberation Organization's (PLO) departure from Lebanon to Tunisia.

Despite this Israeli success in eradicating PLO bases and partial withdraw in 1985, the Israeli invasion had actually increased the severity of conflict with local Lebanese militias and resulted in the consolidation of several local Shia Muslim movements in Lebanon, including Hezbollah and Amal, from a previously unorganized guerrilla movement in the south.

By the early 1990s, Hezbollah, with support from Syria and Iran, emerged as the leading group and military power, monopolizing the directorship of the guerrilla activity in South Lebanon.