Israel began Operation Peace for Galilee on June 6, 1982, after years of attacks by armed PLO factions from Lebanon and a volatile border ceasefire. The June 3 shooting of Ambassador Shlomo Argov in London was the immediate trigger, although Abu Nidal’s group carried it out, not the PLO. Israel’s government described the initial military objective as pushing PLO forces and artillery away from northern Israel; the operation soon expanded far beyond that limited aim.
How the border became a front
Lebanon’s 1969 Cairo Agreement recognized PLO activity in designated areas, while barring fire across the Israeli border. As Lebanese state authority weakened during the civil war, the PLO established armed positions along the border and attacks from Lebanese territory increased. This history is central to the invasion’s security context, but it did not make Lebanon’s many political factions a single actor. Jewish Virtual Library’s history of Lebanon describes the agreement, the growth of armed PLO activity, and the divided Lebanese response.
In July 1981, U.S. envoy Philip Habib brokered a de facto ceasefire between Israel and the PLO after fighting escalated. It reduced cross-border exchanges, but did not resolve the presence of PLO forces in Lebanon or tensions involving Syria. The U.S. State Department’s account of the Reagan administration and Lebanon notes both the ceasefire and the attacks against Israeli and Jewish targets that continued elsewhere.
Argov’s shooting and the invasion
On June 3, 1982, gunmen from the Abu Nidal Organization shot Argov outside a London hotel. Abu Nidal’s faction was hostile to Yasser Arafat’s PLO. Israel’s cabinet authorized military action; on June 6, Israeli forces entered Lebanon. The attack on Argov did not establish PLO responsibility, but it came amid Israel’s stated concern over the PLO’s armed presence and attacks from Lebanon. UN Secretary-General Javier Pérez de Cuéllar’s June 6 report records that the PLO had reaffirmed a commitment to stop cross-border operations after Security Council Resolution 508, while also documenting Israeli air and ground operations that morning. The UN report to the Security Council gives the dated sequence.
The 40-kilometer objective and what followed
Israel initially presented the operation as creating a security zone about 40 kilometers deep, intended to move PLO forces and artillery beyond range of northern Israeli communities. The campaign did not stop at that line: Israeli forces fought Syrian forces in the Beqaa Valley and advanced to West Beirut. The declared opening objective therefore explains the initial rationale, not the entire war or all of its later political aims.
Continue with the major battles at Beaufort, Sultan Yacoub, and the Beqaa, the siege and PLO evacuation from Beirut, Israel’s relationship with the Phalangists and Bashir Gemayel, the Sabra and Shatila massacre and Kahan Commission, the South Lebanon Army and security zone, and the failed 1983 Israel-Lebanon agreement.