The
1982 Lebanon War (,
Al-ijtiyāḥ, "the invasion"), (,
Milhemet Levanon Harishona, "the first Lebanon war"), called
Operation Peace for Galilee (
Mivtsa Shlom HaGalil or
Mivtsa Sheleg) by Israel, and later known in Israel as the
Lebanon War and
First Lebanon War, began on 6 June 1982, when the
Israel Defense Forces (IDF) invaded
southern Lebanon, after repeated attacks and counter-attacks between the
Palestine Liberation Organization (PLO) operating in southern Lebanon and the IDF which caused civilian casualties on both sides of the border. The military operation was launched after
gunmen from Abu Nidal's organization attempted to assassinate
Shlomo Argov, Israel's ambassador to the United Kingdom. Prime Minister
Menachem Begin blamed Abu Nidal's enemy, the PLO, for the incident, and treated the incident as a
casus belli for the invasion.