* In Tunisia, protests have returned 10 years after uprising
* Incident that triggered revolution happened on Dec. 17, 2010
* Wave of protests across region toppled leaders, triggered wars
* Many Tunisians wonder whether sacrifice was worth it
* Economy stagnant, unemployment high, leaving people angry
By Angus McDowall and Tarek Amara
SIDI BOUZID, Tunisia, Dec 15 (Reuters) - Ten years ago, a fruit seller set himself ablaze in the central Tunisian town of Sidi Bouzid after an altercation with a policewoman about where he had put his cart.
Word of Mohammed Bouazizi's fatal act of defiance quickly spread, sparking nationwide protests that eventually toppled Tunisia's long-serving leader and helped inspire similar uprisings across the region - the so-called "Arab Spring".
Huge demonstrations broke out in Egypt and Bahrain, governments fell and civil war engulfed Libya, Syria and Yemen.
Tunisians are now free to choose their leaders and can publicly criticise the state. Yet for all the chaos they have been through, many people look back on the events of 2010 and regret that their dreams remain unfulfilled.
"Something went wrong in the revolution," said Attia Athmouni, a retired philosophy teacher who helped lead the uprising after Bouazizi's death by standing on the fruit seller's abandoned cart to address the crowd the night he died.
Protests have flared again in recent weeks across Tunisia's poorer southern towns against joblessness, poor state services, inequality and shortages.
The scramble to get enough cooking gas to provide for families underlines the hardships ordinary people face in a country where the economy has stagnated, leaving the public as angry as it was a decade ago.
Near Sidi Bouzid last week, a crowd placed large stones across the tarmac to block a main road. They wanted trucks taking cooking gas cylinders to the town to offload them in their village instead.
Supplies have been in short supply in Tunisia since people living near the main state-run factory producing the gas closed the plant several weeks ago to demand more local jobs.
Outside the main outlet for cooking gas in Sidi Bouzid, three riot police vans guarded the gate as hundreds of people waited to get their hands on full cylinders.
A woman at the front of the crowd said she had had no gas for three days and her family had been eating only cold food. She had queued for six and a half hours.
Bigger demonstrations may take place in Tunisia on Thursday, the anniversary of Bouazizi's self-immolation after his fruit cart was confiscated when he refused to move off an unlicensed pitch.
Slimane Rouissi, another Sidi Bouzid activist and former teacher who knew Bouazizi's family, said the young man had endured a string of disappointments before the final confrontation.
He drenched himself in petrol and killed himself in front of the local governorate office.
When Athmouni, the retired teacher, heard about the incident, he dismissed his class and told his students to start protesting.
That night, as hundreds of people gathered outside the governorate and chanted slogans, he heard the words "the people want the fall of the regime" - soon to be the catch phrase of Tunisia's revolution - for the first time.
Over the coming weeks the protests grew. By January, 2011, thousands were marching in Tunis and President Zine El-Abidine Ben Ali, in power for 23 years, realised the game was up. He fled to Saudi Arabia where he died in exile last year.
Tunisia's revolution spread. In Egypt the crowds forced Hosni Mubarak from power after 30 years as president. Uprisings shook Libya, Syria, Bahrain and Yemen.
Hope for a new democratic future soon turned to bloodshed, particularly in Syria, Yemen and Libya, where civil wars pulled in major powers fearful their regional foes would gain an advantage.
Though Tunisia's path to democracy has been far smoother, its economy has deteriorated and political leaders appear paralysed.
Last year's election delivered a bitterly fragmented parliament unable to produce a stable government, with parties bickering over cabinet seats and putting off big decisions.
More Tunisians are trying illegally to leave the country than ever, while visions of jihad lure alienated, jobless youth. Both dynamics were evident in the recent attack in Nice by a young Tunisian migrant who killed three people in a church.
"There is a rupture between the politicians and the people now because the system cannot understand the demands of the street," Athmouni said bitterly in a Sidi Bouzid cafe full of unemployed young men.
In the streets near Bouazizi's old home - a shabby single-storey building behind a dented metal gate - a group of young men stood chatting on a street corner.
Sabri Amri, 26, laughed when asked if he had voted in any of Tunisia's post-revolution elections. All he and his group of friends want is to emigrate, he said. There is no work and young people spend their time drinking or taking drugs, he added.
"We have geniuses here - doctors, engineers. I know a guy who is a mechanical engineer. What does he do now? He sells weed just to live," said Abdullah Gammoudi, a qualified sports teacher who does not have a job.
In Sidi Bouzid, the only tangible signs of investment since 2011 are a new building outside town to replace the governorate headquarters where Bouazizi died, and his memorial - a stone fruit cart scrawled with graffiti saying: "The people want..."
Mohammed Bouali, 37, stood behind the government offices off Sidi Bouzid's main road, his cart full of oranges, apples and bananas. He and Bouazizi used to work on the same street.
Though his work - weighing out fruit for customers with a small hand-held scale - does not make enough to support his two children, he has few other options.
"The government won't provide anything," he said.
The policewoman who confiscated Bouazizi's cart 10 years ago still patrols the same streets, moving unlicensed vendors from their pitches.
Athmouni believes the answer is more protests. Mass uprisings in Algeria and Sudan ousted entrenched leaders there only last year.
"I'm convinced the revolution is continuous," he said. "This year the anger is bigger than in the past." (Reporting by Angus McDowall; Editing by Mike Collett-White)
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