From the mid-1960s Israeli-Lebanese relations began to deteriorate after Palestinian armed factions arrived in southern Lebanon and launched cross-border attacks against Israel. Israel retaliated militarily, in order to try to compel Lebanon to subdue the Palestinians, and subsequently to address Israelās security concerns unilaterally ā ultimately invading south Lebanon in 1978 and establishing a military buffer zone.
Lebanonās civil war (1975ā90) seemed to offer Israel an opportunity to fundamentally change its relations with Lebanon. Israel collaborated with Lebanese Christian militias in the border area from the start of the war and later forged ties with other Lebanese Christian militias in the north. But Israelās 1982 invasion of Lebanon only managed to drive the Palestinian factions out of the country. It did not succeed in establishing a pro-Israeli government in Beirut, nor in guaranteeing the agreement signed between the two states in 1983, which collapsed a year later. Moreover, between 1982ā85, the Israeli army, which occupied substantial parts of Lebanon, began to encounter guerrilla attacks, this time also by Lebanese militias, most notably Hezbollah.
In 1985, Israel decided to establish a formal āSecurity Zoneā in south Lebanon, regulated by a pro-Israeli militia, the South Lebanese Army. But as an Israeli military commander asserts, the result of this development was that āHezbollah transformed from a rejected terrorist organisation, which acts against the wish of the central government in Lebanon, into a legitimate resistance movement of the Lebanese people to the Israeli occupationā. Israel suffered heavy military losses in its struggle against Hezbollah, and subsequent Israeli military operations (Accountability in 1993 and Grapes of Wrath in 1996) failed to tilt the situation in its favour.
Only in 2000, almost a decade after the end of the Lebanese conflict, did Israel decide to cut its losses and withdraw from Lebanon. Even during the war between Israel and Hezbollah in 2006 the Israeli army did not return.