BEIRUT – The demonstration convened yesterday by the terrorist group Hezbollah, a show of force that brought hundreds of thousands of protesters into the streets in support of continued Syrian sway over the country, represents the darkest sign yet that plenty of difficulties lie ahead for Lebanon’s three-week-old democratic uprising.

Roads into the capital were choked with traffic as demonstrators arrived in vans and taxis and on motorbikes, flourishing pictures of the Syrian dictator, Bashar Assad, side-by-side with the white, red, and green Lebanese flag. The gathering was peaceful, the mood festive, the proceedings well organized, and the slogans Orwellian.

“America the Source of All Terrorism,” some placards said, in English. One, in Arabic, said: “Syria = Independence.”

“Not for war, only for peace,” a poster held by a small boy in the thick of the rally said, though Hezbollah, with its long record of murder stretching back to the bombing of the American Embassy here in 1983, remains heavily armed, financed by terrorist sponsoring Iran, and supplied via totalitarian Syria.

At the rally, images of President Assad were everywhere. His face was on placards waved by the demonstrators, his picture, against a sky-blue backdrop, hung high in a tree above the Beirut crowd, and an Assad portrait was replicated in a row of posters near the wrought-iron balcony rails of an otherwise picturesque apartment building.

Adding to the odd carnival feel of the gathering was the din of martial music, blaring in Arabic from loudspeakers such lyrics as “This is the land of 1,000 martyrs.”

The demonstration took place in front of the offices of the United Nations downtown. Along with America and Israel, the chief object of opprobrium was U.N. Resolution 1559. Passed last year, the resolution calls for the withdrawal from Lebanon of all non-Lebanese forces, and the disarmament and disbanding of all militias. Translated from U.N. jargon, Resolution 1559 requires Syria to withdraw its 14,000 or so troops still in Lebanon and requires Hezbollah to give up its weapons. Mr. Assad has said he will comply but has given no timetable. Hezbollah shows no interest in disarming.

From Washington, President Bush has been boosting Lebanon’s democratic movement, and Resolution 1559, almost daily, demanding that Syria withdraw both its troops and its intelligence agents. Yesterday, in a speech at the National Defense University, Mr. Bush said, “I have a message for the people of Lebanon: All the world is witnessing your great movement of conscience. … Freedom will prevail in Lebanon.”

Hezbollah replied with strange definitions of freedom. Surrounded by fellow demonstrators clutching Lebanese flags, a young woman said: “We all want a free Lebanon, as equal democratic citizens” – then expressed at length her support for the Syrian strongman. “We can’t be against Syria when Americans are interfering,” she said. Asked if she thought Syria was democratic, this woman deferred to a burly male companion who stepped forward to declare: “The issue of Syria being a democratic country or not is really an issue for the Syrians.” While he spoke, another protester filed past, carrying a placard that said, in English, “All our problems are from America.”

The highlight of the demonstration was a speech by the Hezbollah leader Hassan Nasrallah, who appeared on a stage high above the crowd to declaim such sentiments as “Death to Israel” and “We are united here above all to thank Syria, the Syrian people, and the Syrian army, which has stayed by our side for so many long years, and is still with us.”

“Like Mussolini” was the response of a Lebanese democratic activist who had come with this reporter to have a look.

The Hezbollah rally took place just a few hundred yards away from Martyrs’ Square, where anti-Syrian protesters have been gathering since the February 14 murder of a former Lebanese prime minister, Rafiq Hariri. Fears are running high of a clash between Hezbollah and the Lebanese who want Syria to leave. To guard against yesterday’s demonstration turning violent, the Lebanese army cordoned off access between the plazas, with heavily armed troops standing before metal crowd barriers, backed in some places by armored personnel carriers.

Pedestrians in small groups were allowed through, but on the anti-Syrian side, there was little to see. Most of the demonstrators who in recent weeks have thronged Martyrs’ Square, sleeping in tents still set up on the site, had chosen on this occasion to stay away. A half-dozen young men sitting on plastic footstools and on the curb near the tents said the anti-Syria crowds would return once Hezbollah had cleared out. Asked if they knew how to use guns, they said no, they are of the generation that grew up after the Lebanon’s 1975-1990 civil war.

“All we want is independence, complete independence,” one of them said. Said another, “We love Lebanon, we live in Lebanon, we will die in Lebanon.”

Near where they were sitting is Hariri’s grave. A large sign set up in front of it flashes a slogan also posted outside Hariri’s house. It says simply, “The Truth.”

The truth about Hariri is problematic. Alive, he was for most of his career no hero of an independent Lebanon, but a tycoon in thick with the Saudi royal family, a man who until recent times pretty much toed the Syrian line. But with his death, he has become something of a symbol of Lebanon’s quest to expose larger truths, after 15 years of living the lies so loudly proclaimed at yesterday’s Hezbollah demonstration.

After yesterday’s rally, two young members of Lebanon’s democratic movement met with this reporter to of fer the view that, as one of them put it, “This country is changing, and we can’t stop it.” They offered a red sticker that says in Arabic, “Independence 2005.”

Sitting in a Lebanese home and watching television footage of the demonstration, a Lebanese who has done time in prison for his democratic activities summed up the slogans in the streets, wondering where it all goes: “So much hate. We hate Israel, we hate America, we hate Syria.” The real question, he said, is, “Okay, but what to do about Lebanon?”

Ms. Rosett is journalist-in-residence with the Foundation for the Defense of Democracies.