Libya crisis: Rebellion or civil war?
Colonel Muammar Gaddafi remains resolutely in power - at least in parts of the country - and appears to be making gains against rebel forces. The BBC's Caroline Hawley asks if the conflict in Libya is looking increasingly like a civil war rather than a rebellion.
Twenty-eight days after Mohamed Bouazizi set fire to himself and sparked the Tunisian uprising, President Zine al-Abidine Ben Ali had fled into exile in Saudi Arabia.
It took just 18 days of street protests to force Hosni Mubarak to step down and fly to the Red Sea resort of Sharm el-Sheikh.
In Libya, Col Gaddafi has pledged to fight to the "last bullet".
The rebels, who have now tasted freedom, are equally determined - if badly outgunned.
"I think this will be a long drawn-out struggle," says Professor George Joffe, an expert on Libya at the Centre of International Studies in Cambridge. "And it's not going to be nice."
Ancient fault line
For the moment, Libya is a divided land. And a fault line runs through the country, between the western half of Libya, largely controlled by Col Gaddafi, and the eastern region that first revolted against him last month.
The front line in the east has shifted up and down the coastal road that runs the width of a vast oil-rich country. But it broadly fits a fault line that has long roots in Libyan history.
The flag that now flies in the east - and areas of the west under opposition control - is that of the monarchy. King Idris, who was overthrown by Col Gaddafi in 1969, hailed from the eastern region of Cyrenaica. In Roman times, Libya was divided into Cyrenaica in the east and Tripolitania in the west, as well as Fezzan in the south.
Cyrenaica's originally nomadic people have a history of rebellion. And Col Gaddafi's policies fed their resentment.
"Gaddafi managed to antagonise the people of Cyrenaica by neglecting the area," says Joffe.
But, in the long term, Professor Joffe doubts that Libya will remain divided. "Everyone now feels Libyan," he says. "Libyans don't want a divided country and Gaddafi won't tolerate it. I suspect that in the end, there'll be an internal coup against him."
'No good options'
For now, Col Gaddafi is fighting back hard against the rebels. But Richard Dowden, author and director of the Royal African Society, does not believe the conflict in Libya will fit the pattern of other African civil wars.
"The idea of a protracted civil war like you have in Congo seems unlikely because of the country's terrain," he says.
"Libya is urban areas and desert - there's nowhere to hide. So it's a simple equation. How much firepower do you have?"
Or how much are you prepared to use? So far, Col Gaddafi has not deployed all his military strength. But the assault on Zawiya, west of Tripoli, marks a significant escalation in his fightback.
In the east, he will also want to ensure that the oil port of Ras Lanuf is firmly under government control.
"Oil is key because it generates all the income that Libya gets," says Prof Joffe.
"Ras Lanuf is one of the main loading points so it controls who gets the oil revenue. But I think the regime has enough resources to carry on for quite a few months."
As the international community wrestles with how to respond, Prof Joffe warns that "there are no good options" for intervention.