What the Palestinian and Iranian cancers did to Lebanon

Until the early 1970s, Lebanon was dubbed "the Switzerland of the Middle
East" for its unique status as both a snow-capped holiday destination and
secure banking hub for Gulf Arabs.[79] Beirut was also nicknamed "the
Paris of the Middle East."[80]

Civil War and occupation
With the 1970 defeat of the PLO in Jordan, many Palestinian militants
relocated to Lebanon, increasing their armed campaign against Israel.
The relocation of Palestinian bases also led to increasing sectarian
tensions between Palestinians versus the Maronites and other Lebanese
factions.

In 1975, following increasing sectarian tensions, largely boosted by
Palestinian militant relocation into South Lebanon, a full-scale civil
war broke out in Lebanon.

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During the early 1980s, Hezbollah, a Shiite Islamist militant group and
political party, came into existence through the efforts of Shiite clerics
who were financially supported and trained by Iran. Arising in the aftermath
of the 1982 war and drawing inspiration from the Islamic Revolution in Iran,
Hezbollah actively engaged in combat against Israel as well as suicide
attacks, car bombings and assassinations. Their objectives encompassed
eliminating Israel, fighting for the Shia cause in the Lebanese civil war,
ending Western presence in Lebanon, and establishing a Shiite Khomeinist
Islamic state.