The price of past appeasement.
That characterization is not exactly fair to Israel with respect to Lebanon. This war with Hizbullah is occurring because the U.N betrayed Israel. Israel invaded Lebanon because of Hizbullah actions, and was universally condemned for it.
In accordance with a U.N. Resolution, Israel pulled their Army out of Lebanon with the assurance that Hizbullah would be disarmed and the Lebanese Army would occupy southern Lebanon.
Lebanon was not allowed by Syria to do this -- Hizbullah moved in with the pretext of providing humanitarian aid to the devastated area. The U.N. did ot insist on it. The U.S. did not insist on it. That is why there is a war today, not because of appeasement, but because of betrayal.