Thirteen years ago, the American Embassy in Beirut sent the Department of State an estimate on the future of Lebanon. The report ran to 31 pages, but it could be summarized in one sentence: Lebanon was living on borrowed time.
This unhappy assessment proved out sooner than expected. The causes of Lebanon's breakup were complex, but the central cause was purely statistical: traditional Lebanon had been dominated by Maronites (Roman Catholics), and Maronites were no longer a majority in the land they called their own. They had been inundated by a combination of Maronite emigration, Muslim and Greek Orthodox population rise, and Palestinian immigration.
Lebanon would probably be under Muslim control today - like every other Arab state - but for two foreign interventions: the Syrians in 1976, and now the Israelis in June 1982.
The brunt of both was borne by those stepchildren of the Middle East, the Palestinians. Civil war broke out in Lebanon between Catholics and the Muslim-Orthodox coalition in early 1975. The PLO was drawn in some months later to bail out its political allies in the coalition. Unsympathetic to the Catholics, the Syrians feared a Sunni-dominated Lebanon even more, so they intervened on the Catholic side. Later, when the pendulum had swung back toward the Catholics, Syria switched to the Muslim-PLO side. It was eventually rewarded - or penalized - by international endorsement as the major element in the force that kept the peace in Lebanon until the Israeli invasion.
As justification for coming in, Israel claimed repeated PLO violations of the cease-fire that the United States and Saudi Arabia arranged along the Lebanon-Israel border in 1981. The Israeli claim does not stand up. Considering the pressure on the PLO to respond to Israeli air raids on targets in Lebanon, PLO observation of the cease-fire had been close to meticulous.
It seems to many outside observers that the Begin-Sharon group invaded Lebanon primarily in hopes of quelling Palestinian nationalist sentiment in occupied Palestine.
Now Syrian forces have been driven back from the coast, Lebanese Muslim-Orthodox forces have been neutralized, PLO forces are bottled up in Beirut, and there is considerable talk of removing all ''foreign '' forces so Lebanon can be independent again. Those who believe this thesis know little about Lebanon. After three decades, no stretch of the imagination can identify Lebanon's Palestinians as foreigners. Whatever they are called, they are not going anywhere.
If the Syrians and the Israelis pull out, the Lebanese balance of forces will revert to that of March 1975, and the conditions will obtain for resumption of the civil war.
Israel probably understands this reality. Indications are its forces will stay on long enough to install a government dominated by the Maronite Phalange. Phalangist leader Ba-shir Gemayel is getting considerable play in the US media as the best hope for president of a resurgent Lebanon.
This idea comes under the heading of thinking impossible things before breakfast. As the longtime recipient of political, financial, logistic, and military support from Israel, the Phalange has identified itself as the enemy of the Palestinians. As an almost exclusively Catholic organization, it is the arch-rival of the Muslims and Greek Orthodox for political control of Lebanon. The whole concept of return to the status quo ante is an illusion in any setting , but most of all in explosive Lebanon.
If a Phalangist is elevated to the presidency, it will be on the points of Israeli bayonets - those same bayonets that were manufactured, delivered, and paid for by Americans. For the sake of its relations with the rest of the Arab world, as well as NATO, the US must look for a better answer.
If it is fortunate, means will be found to remove the PLO forces. However, some foreign force is needed to keep the peace. The United Nations can't provide it; the US won't. Perhaps the Syrians will eventually move back. Otherwise, Israel will be stuck fast to the Lebanese tar baby, and Begin and Sharon will have some explaining to do to the Israeli electorate.