* Syrians have long come to Lebanon for work
* Over 200,000 Syrian refugees already in Lebanon
* Many Lebanese link own civil war to Palestinian refugees
A new video making the rounds in Lebanon opens with ominous string music reminiscent of a horror film and the title "Before it's too late."
Red stains spread across a white map of the tiny coastal country, marking areas where Palestinian refugees settled after they fled or were driven from their homes with the creation of Israel in 1948.
Once settled in Lebanon, the video says, the refugees threatened its sovereignty, attacked its national army and helped cause a 15-year civil war that killed more than 100,000 people. Now Syrians are coming in similar numbers.
"Will history repeat itself?" asks the video, which has garnered thousands of hits on YouTube and been shared on Lebanese blogs and websites.
Some Lebanese said it was racist, but many agreed with it, reflecting concern the fallout from Syria's 22-month revolt against President Bashar al-Assad may threaten the fragile peace between its diverse ethnic and religious groups since 1990.
Those Lebanese see the arrival of tens of thousands of mostly Sunni Muslim Syrian refugees as a replay of the flood of Palestinians which altered Lebanon's communal balance and challenged its Christian-dominated power structure decades ago.
The debate about what to do with the Syrians has raged on social networking websites and in the corridors of power, paralysing the country's response to the influx. Lebanon, unlike Turkey and Jordan, has not set up formal camps for the Syrians.
"In Lebanon, there is no political consensus or national consensus about how to deal with the refugees," Social Affairs Minister Wael Abu Faour told Reuters in an interview.
The camps issue is sensitive because of "historical fears" around the Palestinian camps, he said, while noting the significant difference between the two groups; while the Palestinians were prevented from returning, the Syrians will presumably be able to go home when the war ends.
More than 200,000 Syrian refugees have already arrived in Lebanon, equal to about 5 percent of the country's 4 million population. The United Nations says there may be 1 million Syrian refugees in the region by June, from around 700,000 now.
With an eye on those figures, Energy Minister Gebran Bassil, a Christian, has proposed shutting the border. Other Christian politicians have made similar suggestions. The YouTube video - whose exact origin is unclear - claims that by 2020 Syrian and Palestinian refugees will outnumber Lebanese.
"We must act before we become guests in our own country," it says, urging people to put pressure on politicians to do something, without saying exactly what.
"THERE IS A LIMIT FOR EVERYTHING"
Lawmaker Ibrahim Kanaan is more diplomatic than some of his colleagues when he discusses the refugees. But he is clear about where he stands.
"What's going on in Syria is alarming," Kanaan said in an interview at his home in an upscale northern suburb of Beirut.
What started as a peaceful protest movement demanding democractic reform has become an internationally-backed civil war, he said. "Fundamentalism, Islamism and terrorism" were spreading, and Lebanon could not afford to get involved.
There are few countries where demographics are so sensitive. French colonial rulers carved Lebanon out of Sunni-majority Syria largely to give a haven to the area's Maronite Christians, who follow an Eastern rite of the Roman Catholic church.
The country, only about a third as large as Belgium, is also home to Sunnis, Shi'ites, Druze, Armenians and a medley of other groups. No one knows how exactly how many there are of each because Lebanon has not carried out a census since 1932.
Resentment of Christian dominance among some of these groups helped trigger civil war in 1975. For a decade and a half, rival ethnic and religious factions carved the country into warring fiefdoms and wove a dizzying web of alliances and betrayals. Bullet-scarred buildings still dot the capital, Beirut.
Many Lebanese trace the war's origins to the arrival of tens of thousands of mostly Sunni Palestinians. Over the years, the refugees took up arms to fight Israel but also clashed with Lebanon's army and Christian militias. Tit-for-tat raids and massacres escalated into full-blown war.
For Kanaan, a Maronite, the new influx brings similar dangers. To preserve its stability, Lebanon must distance itself from Syria's conflict, bolster its army and control the border, he said. But he stopped short of calling for the border to be totally closed.
"If we say this, you will have somebody saying, 'Oof, this guy is' - I don't know what sort of description they can give me. But what other solution? If not closed, at least controlled. But controlled seriously," Kanaan said.
"You can receive people, and you have to. And you have to be very sensitive to these issues. But you can't sacrifice your home, your country, your people, just because you want to be humane. There is a limit for everything."
"WHEN THE CALF FALLS, THE KNIVES COME OUT"
Syria and Lebanon's common history and language, as well as family and political ties, mean that in many ways, Syrian refugees have a more complicated situation here than in Jordan and Turkey, the other two biggest hosts.
Before the conflict, many Syrians came to Lebanon to work in construction and farming or to do other manual labour. The line between migrant worker and refugee is often blurred.
Ibrahim El-Eshbee, 27, had lived and worked in the southern Lebanese city of Tyre two years before the conflict began, and decided to return when the war reached his hometown of Idlib in northern Syria.
Peddling vegetables from a cart, he's able to earn enough to afford a spartan two-bedroom flat with several family members. But he says life is harder than the last time he was here. The Syrians' arrival has pushed up rents and deflated wages.
"Before, a house like this used to rent for $100 or $150. Now it's gotten to $200 or $250. It goes up and up. If the landlord isn't happy with the rent, he'll kick out the tenant and rent the place to any family that's desperate," Eshbee said.
The conflict has also cut off supply routes for cheap goods from Syria the vendors used to sell. "Now there's nothing from Syria, and the parts from China are too expensive," he said.
Down the road in a dirt lot near the Mediterranean coast, Syrian families crowd into tents made of plastic sheeting and weighed down by tyres and breezeblocks. Signs for a McDonald's and a large supermarket loom in the distance.
A cultural centre across the street is named after Bassel al-Assad, the Syrian president's late brother, a reminder of the ties between Syria's government and Hezbollah, the political and military group which dominates the largely Shi'ite area.
Hezbollah have said the refugee issue is humanitarian, not political, and should be treated accordingly. Indeed, Syrians in the Tyre camp said they had no political disputes with locals.
Economic relationships were another matter.
"We've gone back to the days of slavery," said one young man from the northern Syrian city of Aleppo with a light black beard, a leather jacket and long, slicked-back hair.
"The Lebanese come to you, and they don't treat you like you're a person. There are no human rights. 'You're a migrant, you're a refugee, you're a labourer.' It's like that."
Refugees at the camp said they paid the lot's owner 50,000 Lebanese pounds ($33) a month per tent, while the wage for a day's labour had dropped from 15,000 pounds to 8,000 -- little more than a grilled chicken sandwich at a nearby store.
"We have this Arabic expression: 'When the calf falls, the knives come out.' The butchers come out. Now we're like the calf," said the Aleppan man, who declined to give his name.
"A SOCIAL EXPLOSION"
The resentment cuts both ways. Many Lebanese complained about Syrians opening up shops and competing with locals, Abu Faour, the social affairs minister, said. Others had found jobs scarcer and wages lower because so many Syrians were now willing to work for so little.
More children and beggars have appeared on the streets, Abu Faour said. The delay in setting up camps meant around 220,000 Syrians had scattered throughout some 700 sites in Lebanon, costing resources to monitor and protect them.
"I'm afraid this issue could lead to a social and economic explosion in Lebanon," Abu Faour said.
Gunmen loyal to opposing sides in Syria's civil war have clashed repeatedly in Lebanon's second city Tripoli, where posters of Assad cover walls in some neighbourhoods. On Friday, at least two Lebanese soldiers were killed in a gunfight with militants, which residents said was linked to Syria's conflict.
Robert Watkins, United Nations humanitarian coordinator for Lebanon, said resentment against the Syrian refugees was indeed growing. In the northern Akkar province, someone recently lobbed a Molotov cocktail at a Syrian gathering.
Still, Abu Faour said, Lebanon's government will eventually have to consider setting up camps, despite the resistance to such a move. "Today, this issue has become pressing," he said. "There is no longer anyone who can ignore it."