Washington ? Lebanon, when I lived, there was a simmering cauldron that I watched explode into vicious civil war in the spring of 1975. Thirty years have not dimmed my regard for the Lebanese people or my regret over their fate. Trusting their political instincts still comes hard, however.

This is to take nothing away from the hundreds of thousands of demonstrators who have seized the streets to protest the ill-begotten Syrian occupation of their land. These outpourings have taken, and demonstrated, courage and a national unity long absent from Lebanon.

Nor should we quarrel with those who portray this embryonic Beirut Spring as a positive step in the democratic transformation of the Middle East. This is a moment that should be celebrated, supported and expanded, as President Bush suggested by predicting on Tuesday that “the thaw has begun” for the region.

But it is also a moment to keep expectations from racing too far ahead of Lebanon’s complex reality and the differing views that its troubles still provoke from outside powers, principally France and the United States.

The best way to aid Lebanon’s rebirth as a nation is to keep the focus on the intricate set of political negotiations over power-sharing that the Lebanese themselves must initiate, manage and make succeed once the Syrian boot is off their collective neck.

Each of Lebanon’s three large population groups — Christians, Sunnis and Shiites — has competitively and disastrously relied on outsiders to provide a margin of domination that none can achieve alone. The United States can help most by catalyzing and then shielding the process of reconciliation from outside interference, as it now does by pushing the Syrians to leave.

Overreaching because of early, inflated optimism is to be avoided not only for Lebanon’s sake, but also for the sake of the larger U.S. project for regional transformation.

Exaggerated optimism about Iraq gave rise to post-invasion bitterness and exaggerated pessimism inside and outside the administration. The overreaction — the swift, continuing alternation in perception between “success” and “failure” — obscured the need for a speedy transfer of responsibility to Iraqis and helped delay elections there. The political runways in Iraq were overshot, successively, in opposite directions.

Something similar could easily happen in Lebanon, a country that provides a study in contrasts, physical and political, as I kept hearing as I prepared to move there for The Washington Post in 1972:

You can ski down snowy slopes in the morning to swim in the Mediterranean at lunch. Lebanon contains the Arab world’s most energetic, resourceful and warm people — until their divisions and hatreds explode into internecine butchery.

These foreign-correspondent stereotypes captured a split-level reality that civil war, Syrian occupation, great-power neglect and now this effervescent moment of political change have not erased. Anything is possible in Lebanon.

But the country’s deep social chasms make Lebanon a weak reed for the Bush administration to lean on in pursuing its Greater Middle East ambitions. Those in search of historical analogies may eventually have to consider Europe’s promising but stillborn revolutions of 1848 instead of the collapse of the Soviet empire and the Berlin Wall in 1989 as the model.

Initially successful uprisings in France, Germany, Hungary, Italy and elsewhere in 1848 were reversed by new authoritarian governments. But to say the revolutions “failed” is to misread history. The impulses they generated continued to course through those societies and guide them toward national unity and democracy long afterward. A rush to judgment concerning the coming difficult weeks in Lebanon may also miss their fundamental importance.

In the past century, Lebanon was an influential intellectual and political catalyst in the Arab world. Events have placed restoration of that role within reach — if Syrian withdrawal and its aftermath are managed tenaciously and with vision. And that outcome would reinforce the waves of change that regime change and elections in Iraq have provoked.

France and the United States have found common cause to press Syria’s Bashar Assad to withdraw troops first sent to Beirut in 1976, with the approval of both powers. “Paris wants to stabilize Lebanon, and Washington wants to destabilize Syria,” a diplomat in Europe said to me recently. “There’s something for everyone.”

The hard work lies ahead, as Assad predictably tries to buy time with vague promises and muscle-flexing through his Hezbollah allies. But the key judgment made by the Bush administration in the spring of 2002 — that the political status quo could not and should not be maintained in the Middle East — is being proved prescient and worth pursuing through this Beirut Spring.

— Jim Hoagland is a columnist for Washington Post Writers Group.