With a Shiite-Sunni sectarian war brewing along the Syrian border, few Lebanese might want to remember the Israeli invasion of 1982, which started 30 years ago today. Yet that war and its sequels not only changed the balance of power in Lebanon but also set the stage for the regional power struggle across the Middle East today.

Israel’s key war aim was to flush the Palestine Liberation Organization out of southern Lebanon, thus dismantling Yasser Arafat’s fiefdom known as Fatahland.

The Shiites of Southern Lebanon, the majority in the area, would become the chief beneficiaries of the Israeli victory. This is why they greeted units of the Israeli Defense Force with flowers and sweets.

Few imagined that within less than two years, Fatahland would be replaced by an even more hostile “Imamistan” — a fiefdom controlled by Hezbollah, acting as Iran’s cat’s paw.

To deal with that unintended consequence of its victory, Israel had to hang on to a strip of territory inside southern Lebanon for two decades, at enormous cost in blood and treasure.

Israel’s second objective was to capture or kill Arafat and coterie. It didn’t — because the United States, acting with UN approval, intervened militarily to escort Arafat and hundreds of his associates out of Beirut and into safety. And the massacre of Palestinians at Sabra and Shatila, although carried out by the Phalangist militia, provided Arafat and his clan with a new addition to their anti- Israeli narrative of victimhood.

America and its chief ally in that intervention, France, paid heavily for breathing fresh life into the moribund Palestinian cause: Some 241 US Marines and 57 French paratroopers were murdered in suicide attacks organized by Iranian and Syrian agents in Lebanon. In the following decade, 23 American and French citizens were a held hostage by Hezbollah on orders from Tehran and Damascus, and three were murdered.

Israel’s third objective was to impose Bashir Gemayel, a Maronite militia commander, as president of Lebanon, hoping to have a friendly neighbor to the north. Once again, a seemingly easy victory quickly turned into a setback: Gemayel became president — but only for a brief moment before he was murdered by Syrian agents.

Already mired in civil war, Lebanon quickly degenerated into a badland where terrorism, kidnapping, drug-smuggling and gun-running became industries employing tens of thousands of people. The civil war would last another decade in its intense form — and, in a sense, continues to this day.

The 1982 war marked the start of a process in which Israel has been sucked into asymmetric war against militias controlled by regional powers. At different times, Libya under Col. Khadafy, Iraq under Saddam Hussein and the Arab oil kingdoms financed and armed different armed factions in Lebanon. Iran and its main Arab client Syria still do so today.

Thirty years later, Lebanon poses a serious threat to Israel’s security. Yesterday, the official Iranian news agency, IRNA, boasted that the Islamic Republic had supplied Hezbollah with thousands of short- and medium-range missiles capable of “hitting every single spot” in Israel. It also claimed that 30,000 Hamas fighters and 5,000 “holy warriors” from the Islamic Jihad, based in Gaza, were getting ready “for the final battle with Zionism.”

Militarily, Israel achieved a clear victory in Lebanon in 1982. But its leaders couldn’t translate that victory into lasting political gain. Part of that was due to UN intervention, which was (as always) designed to prevent Israel from cashing its chips, as it were. But another part was Israeli leaders’ failure to see beyond the tactical changes that their victory had produced.

The war was a game- changer in the sense that it turned Lebanon into a battleground between Iran and Syria (backed by Russians) on one side and the United States, with its Arab allies plus Israel, on the other.

Today, Lebanon remains a major strategic prize — control of which could impact the conflict in Syria and the prospect of change in Iran. (Copyright 2012 NYP Holdings, Inc. 06/06/12)