|Yemen has a long history of internal violence, experiencing a string of civil wars since the 1960s [GALLO/GETTY]
Ali Abdullah Saleh, Yemen's president, is coming under increasing pressure to step down. A wave of resignations and defections, from tribal, military and political leaders, have severely undermined his leadership in the face of growing protests.
But, similar to the revolution in Egypt, Yemen's opposition movement has not been spearheaded by a strong figurehead, raising questions as to what or who could take power in Saleh's place.
The president has warned his country that any "coup" against his rule would lead to "bloody civil war" in Yemen, which is challenged by a secessionist movement in the south, sectarian conflict in the north and severe poverty.
Western nations also fear that chaos in Yemen could allow Al Qaeda in the Arabian Peninsula (AQAP) to flourish, and that a failed state bordering Saudi Arabia and a major shipping route could pose an international threat.
Michael Binyon, foreign affairs expert at The London Times newspaper, believes these fears are justified in a country "used to general conflict".
From the 1960s Yemen has been hit by civil war and violence, often due to divisions political ideology and severe poverty. Known in Roman times as Arabia Felix - meaning wealthy and fertile - Yemen is now the poorest country in the region, and could be the first nation in the world to run out of water.
"Most Western nations don't care about Yemen because it's poor, and most people are zonked on Qat. But they are worried about the security implications," Binyon said.
"Saudi Arabia is hugely concerned with what's going on in Yemen, they're absolutely terrified. Yemen has 24m people, that''s a lot of people on your doorstep, and this is just the latest in the set of dominoes in the region to fall.
"It's also only just across the water from Somalia, which is another failed state, so you could have two failed states across a major shipping route."
These fears, however, are not stopping the protesters calling for Saleh to resign.
According to Gregory Johnsen, a Yemen expert at Princeton University, "most Yemeni's are no longer buying this argument" that their leader stands in between peace and chaos.
He says that the Houthis - the Zaydi Shia group in the north, and the secessionists of the south will "all play a role in the future of the country".
"All those groups want Saleh to step down. They want different things - and that's going to be a real challenge - how these groups will be able to work together. But people aren't talking about that now because they want to present a unified front against Saleh."
A strong culture of mediation in Yemen could allow this to happen, he says. "Houthis and secessionists need to be reconciled and to come into the fold. Most people realise this."
Hakim Al Masmari, editor of the Yemen Post, also believes that a transitional government, possibly one run by the military, could bring Yemen's different groups together and save the country from violence.
"The military don't want to rule. The Houthis all confirm that there must be a transition strategy that could take place so that the ship will not sink.
"We talked to a representative of the southern secessionist movement - he told us their demands is that the regime must be let go ... they don''t think that the situation can get any worse than it is now."
''Kingmakers, not kings''
But in a tribal country like Yemen, where most people are allied to different groups, is there a real prospect of a viable alternative?
Some five or six years ago, US diplomats in Sanaa, the Yemeni capital, concluded that Saleh had been "so successful at co-opting or eliminating his competition that few viable alternatives to his leadershp exist at the moment".
In embassy documents released by Wikileaks and published by The Guardian newspaper, a diplomat wrote: "When asked names for potential successors, Yemenis are unable to come up with a single potential candidate. Despite yearnings for a genuine democratic process, most believe that the next president will come from within Saleh's inner circle of family and military allies."
They named Sheikh Abdullah al-Ahmar, who headed Saleh's Hashid Tribal Confederations, and General Ali Mohsen al-Ahmar, the country's most powerful military leader, as being second to Saleh.
But Ali Mohsen, and al-Ahmar's son and successor Sadiq, have defected in recent days, and analysts believe neither of them likely presidential candidates.
But Johnsen is cynical of this conclusion.
"Just because the US embassy in Sanaa says there are no viable alternatives doesn't mean there aren't other alternatives. There are a number of individuals who could step in, the challenge is finding one with broad appeal.
"Ali Mohsen and Sheikh al-Ahmar are unlikely to stand to president, but they might sit on a trusteeship council and help manage the transition."
Abdulalem Alshamery, editor of the Yemen Voice, a British-based publication, said Yemenis want to see "new faces, educated young people, to take power".
While he believes that the Houthis could be integrated into the political sphere, he is less certain that other groups can put their aims aside to form a working government.
"The separatists in the south are waiting for Yemen to fall apart so that they can go back to the south. They are not asking for separatism now, they are supporting the youth movement.
"But once Saleh steps down they will push for separatism again. They will use violence again and the military will intervene," he said.
Alshamery adds that al Qaeda, although an "exaggerated" threat used by Saleh to "manipulate funding into his regime" could also affect the power struggle in Yemen.
Most analysts tend to agree that while it's hard to gauge the full extent of al Qaeda's numbers in Yemen, the group, or people who share the group's beliefs, do pose a threat to the country's stability and political life.
Yemen is still home to Anwar al-Awlaki, identified by the United States as a radical cleric linked to extremists behind violent plots, and Al Qaeda in Yemen has claimed responsibility for a number of attacks, both in the country and against Western targets.
Justin Crump, CEO of Sibylline, an international security risk and intelligence consultancy, says that while AQAP may just number a few hundred people, they are "reasonably ambitious" and see Yemen as strategically important for operating against Saudi Arabia.
He believes they could use the current crisis to recruit more members, as "people are going to turn to alternatives amongst the chaos".
"They already have a lot of tribal support, especially after the US missile attacks in recent years."
But he said regardless of support for al Qaeda or any other group, none of it will solve Yemen's problems of poverty, lack of water and resources. Even the issue of Qat, which takes up so much of the country's water resources, could overshadow the threat posed from al Qaeda.
The main problem facing the country right now, Gregory Johnsen argues, is whether the president agrees to go peacefully or stays for the fight.
"What comes next in Yemen will be determined by the style and timing of Saleh's exit," he said.
"The question is whether he steps down peacefully, hands over to a transitional government, or digs his heels in and refuses to go, which will lead to violence."