What happened
Lebanon's army commander and the PLO sign an Egyptian-brokered agreement regulating Palestinian armed activity from Lebanese territory. After the PLO's expulsion from Jordan in 1970–71, Lebanon becomes its principal base, and southern Lebanon a front with Israel.
It made the Lebanese state's monopoly of arms a negotiated exception decades before the Hezbollah question, and turned the Israel–Lebanon frontier from a quiet armistice line into an active front. The Lebanese civil war from 1975 and every Israeli operation in Lebanon from 1978 run through the space this agreement opened.
Confidence: High
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