There is a moment in Gillo Pontecorvo's masterful film the Battle of Algiers, which portrays the Algerian struggle for independence in the 1950s, when one character makes an observation that has echoed down the decades since. "It's hard enough to start a revolution, even harder to sustain it, and hardest of all to win it," he says. "But it's only afterwards, once we've won, that the real difficulties begin."
It's a lesson bitterly learned in the tumultuous four years since a frustrated young Tunisian fruit seller named Mohamed Bouazizi set himself alight, triggering protests across the region that would eventually topple three dictators. From north Africa to the Levant and the Gulf, the tremors from that spring of 2011 continue to make themselves felt, despite a return to military rule in Egypt and civil war in Libya, Syria's continuing spiral and the Gulf monarchies' wariness of any sign of dissent. Only Tunisia seems to have emerged from the tempest in better shape than it was before, its transition from dictatorship to democracy underpinned by a political consensus that remains a model for those who hanker for change elsewhere.
Last November, octogenarian Beji Caid Essebsi triumphed in the Tunisia's first free and fair presidential elections. Key to Tunisia's progress - the lone success story of 2011 - is the way he and other politicians, both Islamist and secular, have strived to put the country's interests above party politics to forge a more inclusive path forward.
A poster child Tunisia may be but the challenges it faces remain profound. In March, militants gunned down 21 tourists at the Bardo museum in Tunis, a grim reminder of the violent extremism that threatens so much of the region. While Tunisia has succeeded in establishing a working democracy from the ashes of totalitarian rule, this has not been enough to stem a drift towards radicalisation among the country's youth. It is estimated more Tunisians than any other nationality have joined ISIS in Syria and Iraq.
The fact the country that birthed what became known as the Arab Spring is also the country that produces the largest number of fresh-faced fighters for ISIS points to a key driver of the revolutions and uprisings that swept the region four years ago: disaffected youth.
The chants that inspired the protests of 2011 called for many things: freedom, democracy and above all dignity. For millions of unemployed young people across the Middle East and North Africa, a dignified life meant a job that would provide the means to allow them to marry and raise a family.
Today the problem of youth unemployment is even worse than it was before. Across the region, the jobless rate for young people stands at 29.5pc, the world's highest, an increase of two percentage points in more than a decade, according to the International Labour Organisation.
Before the protests of 2011 erupted, the UN Development Programme (UNDP) warned 51 million jobs needed to be created by 2020 to cater for the youth that comprise some two-thirds of most national populations across the Middle East and North Africa. Few among the region's greying leaders appeared then - or indeed now - to realise the challenges or opportunities presented by this youth bulge.
The ways of old - subsidies designed to keep a lid on discontent while outmoded educational systems produced graduates fit only for the already bloated public sector - remain in place but the social contracts which previously held it all altogether are in a state of collapse.
Many educated young Arabs are desperate to leave their home countries, the disconnect between their aspirations and reality all the more painful now that they tasted possibility in those heady early months of 2011.
The UNDP says the regional "brain drain" is gathering pace. It estimates the number of young Arabs who have voted with their feet and taken up work and education opportunities elsewhere has almost doubled since 2012.
Those who have no other choice but to remain face even bleaker prospects than four years ago with economies even more hobbled due to low oil prices and impact of prolonged conflict across the region. Widespread unemployment coupled with the dashed expectations of recent years risks creating fertile ground for militants, particularly ISIS, as it seeks to draw recruits for the caliphate it has declared across vast tracts of Syria and Iraq.
"If you're young with no job and no hope then of course ISIS can be appealing," says one Libyan whose childhood friend ran away to join ISIS. "What ISIS promises is a way out, a chance to be part of something bigger than you are."
While Tunisia is proof that a democratic transition from dictatorship is possible, Egypt offers a very different lesson, one that has caused many to question if true democracy will ever take root elsewhere in the region.
Abdel-Fattah Sisi, the Egyptian army chief who ousted Mohamed Morsi in a coup two years ago and was later elected president, now heads a military regime with a thin democratic veneer. The military overthrow of Morsi, a member of the Muslim Brotherhood and Egypt's first democratically elected president, while supported by a great many Egyptians, sent a damaging message. "Now when we try to convince the radicals to embrace democracy, they turn to us and say, look what happened to Morsi," says one Libyan who mediated with the extremist groups that flourished amid that country's security vacuum.
Sisi's rule has been marked by severe repression. The Muslim Brotherhood has been declared a terrorist organisation and outlawed. Many of its leading members, including Morsi, have been sentenced to death. Thousands of dissidents - not all of them Islamists - have been rounded up and media organisations threatened. With former president Hosni Mubarak exonerated of the most serious charges against him, it is not uncommon to hear Egyptians say their revolution is dead.
The aftershocks of Morsi's ousting were key to Libya's unravelling. Libyans hoping to see a similar scenario unfold there endorsed retired general Khalifa Haftar, who was accused of attempting a coup in February last year. He later resurfaced in eastern Libya and declared war on militias in Benghazi, a city which had been wracked by assassinations and bombings. While Haftar publicly played down his ambitions, some of his prominent backers openly talked of him as a "Libyan Sisi". He drew support from Libyans fed up with deteriorating security, but also some who hankered for a potential strongman who could impose order on the post-Gaddafi chaos.
On election day last July, I met several Libyans who said security was more important to them than democracy. The turnout that day - for Libya's second parliamentary elections since Gaddafi's fall - was just over 600,000, a dramatic and telling drop from the 1.7 million who had voted in the 2012 ballot. Many Libyans have grown disillusioned with their country's fraught experiment in democracy, believing real power is vested not in elected institutions or state bodies but in the constellation of militias that sprang up during and after the 2011 revolution.
A weeks-long militia battle in Tripoli last summer contributed to the current impasse where two rival governments - one internationally recognised and based in eastern Libya and the other self-declared in the capital - are engaged in a political power struggle which has erupted into fighting between armed factions aligned with each side. Haftar is now commander in chief as appointed by the internationally recognised parliament and is seen as an obstacle to UN efforts to forge a deal leading to a unity government. Fighting continues in Benghazi, cradle of the 2011 uprising, between Haftar's forces and their opponents, who now include ISIS. Fighters from across the region have come to join ISIS in Libya, seeing opportunity in the country's turmoil. One resident of the city told me he had given up on his hopes of ever seeing the Libya he always dreamt of. "My young children might see it, but I will not," he said. "I often wonder did we fail our revolution or did our revolution fail us."
On December 17, 2010, Mohamed Bouazizi, young street vendor frustrated by police harassment, set himself on fire in the town of Sidi Bouzid and later died in hospital. His death triggered protests across the country and on January 14, 2011, popular pressure forced long-time president Zine El Abidine Ben Ali to flee the country. Tunisia has since weathered political tumult and jihadist violence, but succeeded in adopting a new constitution in January 2014. Last October, Nidaa Tounes, a party containing figures who were close to the Ben Ali regime, triumphed in legislative elections. One of its members, Beji Caid Essebsi, subsequently won in the country's first free and fair presidential elections.
Four years after anti-regime protests swept Syria, the country has been devastated by a vicious civil war that has resulted in the deaths of more than 200,000 people, forced half of the country's population to flee their homes and destroyed much of its infrastructure. Radical groups such as the al-Nusra Front, an al-Qaeda affiliate, and ISIS have gained ground as forces loyal to President Bashar al-Assad continue to try to snuff out the revolt against him. Since last September, a coalition comprising the United States and regional allies has carried out air strikes against ISIS but this has failed to stem the organisation's advance across Syria and neighbouring Iraq. The resulting exodus of refugees across Syria's borders has put neighbouring Turkey, Jordan and Lebanon under severe strain.
Inspired by Tunisia, popular protests erupted across Egypt in January 2011, forcing Hosni Mubarak to step down from the presidency on February 11, 2011 after almost three decades in power. In June 2012, Mohamed Morsi, a member of the once-banned Muslim Brotherhood, became the first civilian and freely elected president of Egypt. But Morsi's presidency was marked by controversy and dissent, and he was ousted by the military led by Abdel Fattah Sisi in summer 2013. A brutal period of repression followed: more than 1,400 people, mainly Morsi supporters, have been killed in street clashes and 15,000 arrested, including the former president and most of the Muslim Brotherhood leadership. Hundreds, including Morsi, have been sentenced to death. In June 2014, Sisi won a presidential election, while the most serious charges levelled against Mubarak have been quashed.
After a year-long popular revolt, long-standing president Ali Abdullah Saleh stepped down in February 2012 in a deal brokered by the United Nations and Gulf Cooperation Council. He is now aligned with Iranian-backed Houthi rebels who seized the capital Sanaa last September before advancing into central and south Yemen. This has pitched Yemen into a battle between the Houthis and Sunni tribesmen, with al-Qaeda militants also on the anti-Houthi side. Yemen became a fully-fledged regional proxy war in March when a Saudi-led coalition began air strikes on Houthi targets, seeing them as a conduit for Iranian influence. The Saudi-led alliance wants to see president Abd-Rabbu Mansour Hadi restored to power.
The uprising against Muammar Gaddafi was the only revolt of the Arab Spring where the international community intervened decisively. Gaddafi's violence and threats against his own people prompted a UN resolution mandating a Nato-led intervention aimed at protecting civilians. Since Gaddafi's demise at the hands of rebel forces in October 2011, Libya's transitional authorities have struggled to impose order. Four years on, the country remains awash with weapons and pulled in several directions by the constellation of militias that emerged during and after the uprising. A weeks-long militia battle in the capital Tripoli last summer resulted in two rival parliaments and governments - one internationally recognised and based in eastern Libya and the other self-declared in Tripoli. Armed factions aligned to each continue to fight in different parts of the country.
The tiny Gulf kingdom's delicate sectarian balance unravelled in February 2011 when Shias - who form the majority of Bahrain's population - took to the streets demanding rights. The protests were brutally snuffed out by forces loyal to the ruling Sunni al-Khalifa monarchy but Bahrain remains tense today. The opposition, which calls for a proper constitutional monarchy, boycotted parliamentary elections in November 2014 after the government dragged its feet on reforms. Torture and jailing of activists continues, according to human rights groups.