Four years ago, Ayman Askar was in a prison in south Yemen, serving a life sentence for murder. Now he is a wealthy and important man whose friendships cut across the many lines of the fragmented civil war that has destroyed the country. Askar has recently been named the chief of security for a large district in the southern port city of Aden – appointed by the government of Yemen, on whose behalf Saudi Arabia has been bombing the country for three-and-a-half years. But Askar is also a friend and ally of the United Arab Emirates – the most aggressive partner in the Saudi-led coalition fighting to restore the government of President Abd-Rabbu Mansour Hadi, who was forced from office by the Houthi rebellion in 2015.

The Saudis have attracted the bulk of the world’s displeasure for their bloody intervention in Yemen, but the UAE plays a more forceful role on the ground – and its allies in the south, including local militias, Salafi fighters, and south Yemen separatists who want to break away from Hadi’s government, have been known to fight against the Saudis’ own proxies in the country.

Today Askar is allied with the government of Yemen and the UAE, but not long ago he was a member of al-Qaida, the enemy of both. Thuggish and heavy-set, with a bull-like head on strong, wide shoulders, he jostled his way up the power hierarchy of prison life: he ran a grocery store in the prison yard and a PlayStation lounge in one of the cells, and befriended the strongest gang in the prison – a group of al-Qaida inmates. He prayed with them, attended their classes, grew his beard and started dressing like them, although his friends say he never joined the organisation properly because he is too opportunistic to pledge allegiance to a single cause.

When Houthi fighters from north Yemen, backed by Iran, invaded the south and toppled the government in the capital, Sana’a – forcing Hadi to flee south to Aden, and then abroad to Saudi Arabia – Askar was still in jail. But in the chaos that followed, al-Qaida fighters stormed the prison and freed its inmates. Askar joined the resistance and fought against the Houthi invaders alongside his jihadi friends, distinguishing himself as a ruthless field commander and dividing his time equally between fighting and looting.

A few months later, the Houthis were driven out of Aden by a combination of local militias, southern separatists, government forces and UAE and Saudi troops. Askar expanded his interests beyond jihad, imposing a protection racket on the port and extorting a commission from every shipment that came through. The government issued a series of arrest warrants, but he weathered them all. He soon befriended the Emirati officers who had arrived as part of the forces that took over the city – and he spent long stints in Dubai and Abu Dhabi, making connections. He was rewarded for his friendship with a lucrative transportation contract, and has since moved into the profitable business of looting large swaths of farmland around Aden.

In the summer I met Askar as he entertained friends on his farm north of Aden. The farm was lush, green and quiet – worlds away from the crowded, suffocating streets of Aden. With the bonhomie of a bandit, he joked and told stories from his last trip abroad. He and a friend had rented three Mercedes vans with their drivers, to ferry them and their wives and children around the resorts of Sharm el-Sheikh in Egypt, taking them to water parks, beaches and seafood restaurants.

“It was a week from heaven,” Askar told the friends gathered around him. “The children were very happy, and one could forget about all the troubles of war.”

Ayman Askar is just one of the people who have done well from the war in Yemen – a conflict the UN has called the world’s worst humanitarian crisis, with at least 14 million people now estimated to be at risk of starvation. Last week, UN-sponsored peace talks in Sweden produced a temporary ceasefire between the Houthis and pro-government forces in the Red Sea port of Hodeidah, a crucial gateway for humanitarian aid into the country. The Houthis have controlled the city since 2015, but it has been under assault for months by Saudi-UAE coalition forces, leading to warnings of an even worse humanitarian catastrophe.

If the fragile ceasefire holds – which is not certain – both sides will be required to withdraw their troops from the port. A successful truce in Hodeideh could pave the way for progress at the next round of talks, scheduled for late January. But the war is not yet over.

In fact, it is no longer even a single war. It began as a conflict with two clear antagonists – the Saudi-led coalition allied with the government versus the Houthi militia supported by Iran. But the force and funding of outside intervention – especially from the UAE – has helped to fragment the war into multiple conflicts and local skirmishes that will not necessarily be ended by any peace agreement. Yemen is now a patchwork of heavily armed fiefdoms and chaotic areas, where commanders, war profiteers and a thousand bandit kings, like Ayman Askar, thrive.

There is a regional war between the north and the south – which were separate and often warring states before 1990. There is a sectarian conflict between Zaidi Shias, such as the Houthis, and Sunni Salafis. Beyond these major fault lines are many smaller conflicts, inflamed and aggravated by the money and weapons supplied by outside forces to anyone seen to advance their agenda.

The government of Yemen – with scores of ministers and deputy ministers – is dysfunctional and corrupt, and since 2015 has been in exile in a Saudi hotel compound. It has an army of more than 200,000 troops, although many of them haven’t been paid, or exist as ghost soldiers – names on a list, whose salaries are siphoned off by their commanding officers.

The Saudi-led coalition itself is riddled with conflicts and rivalries, with each of its principal members following a separate agenda and plotting against the others. In Taiz, a city in central Yemen that has been besieged and shelled by the Houthis for more than three years, the fighters on the coalition side are split into more than two dozen separate military factions – including local militias backed and sponsored by the UAE, as well as al-Qaida and other jihadis. Some fighters switch sides according to who is offering funds.

Two years ago, when a tribal Sunni sheikh from Bayda – on the traditional fault line between the Zaidi north and the southern Sunni lands – went to seek assistance from the UAE in his battle against the Houthis, an Emirati general told him that the Houthi rebels “are no longer our priorities or biggest enemy”. The sheikh was told that if he wanted weapons from the UAE, he also had to fight Islamic State (Isis), al-Qaida and al-Islah – an Islamist political party that plays a dominant role in the very same government the UAE has ostensibly sent troops to Yemen to defend.

Now there are three different forces fighting across the sheikh’s territory, each supported by one or even two of the main factions in the coalition: the UAE, the Saudis and the government of Yemen. Each army in this region of ragged hills and black volcanic stones has received millions of dollars’ worth of military equipment, trucks and salaries for the fighters. Meanwhile, farmers in these same lands can no longer afford to buy petrol for their tractors; they straggle behind scraggy donkeys pushing wooden ploughs while their children become fighters and militiamen.

The Emiratis appear to be the only alliance members with a clear strategy. They are using private armies that they have created, trained and funded in a bid to crush both jihadi militancy and Islamist political parties such as al-Islah. Across the southern coast – where the UAE is allied with the separatist Southern Movement, which is opposed to both the Houthis and the Hadi government – the Emiratis have built a series of military camps and bases, and established what is essentially a parallel state, with its own security services who are not accountable to the Yemeni government. Amnesty International and Human Rights Watch have revealed the existence of a network of secret prisons operated by the UAE and its proxy forces, who are accused of disappearing and torturing al-Islah members, anti-Houthi fighters from rival factions, and even activists and critics of the Saudi-UAE coalition. Yemeni ministers have taken to referring to the Emiratis as an “occupation force”.

The Saudis’ floundering military strategy has largely involved relentless bombing of civilians. Their blockade of Yemen’s ports has pushed millions of people to the edge of starvation. In the last couple of years they have been reduced to playing the role of a peacemaker between their two allies, the UAE and the government of Yemen.

“We had hoped that the Saudis would intervene to stop the folly of the Emiratis, but they are lost,” a Yemeni commander based in Aden said to me last summer. “The war is not going well for them, and they can’t be bothered with what’s happening in the south, so they have handed that file to the Emiratis.”

What the Emiratis have achieved in Yemen – creating private armies, propping up secessionists in the south and conspiring to destroy the political system, while controlling strategic waterways in the Arabian and Red seas – shows how a small and very ambitious nation projects its power in the region, and the world.

The devastating civil war that began in 2015 was years in the making, but the biggest spark was lit around 2011, amid the exuberance of the Arab spring, when a popular protest movement drove former president Ali Abdullah Saleh from power. Saleh had ruled through an intricate system of corruption and patronage for three decades, but unlike other deposed Arab dictators he did not go to prison or flee the country. Instead, a delicately negotiated settlement, brokered by the UN and Yemen’s Gulf neighbours, allowed him to step aside and avoid prosecution while Hadi, his vice-president, took over. But while representatives of the country’s various factions debated a political transition in the capital, in the north and the south some of these same tribes and parties were fighting to impose their will on the ground, tearing the country apart and thrusting it toward another civil war.

Of these many feuding powers, the Houthis, or Ansar Allah, as they called themselves, were the most organised and ideologically driven. They believed they had a divine mission. Hussein Badreddin al-Houthi, the movement’s founder, was a Zaidi religious leader who attacked the corruption of the Saleh regime and preached a millenarian melange of anti-western ideology and Islamic revivalism. (The Zaidis, a Shia sect largely located in Yemen, represent about a third of the country’s population, but their brand of Shi’ism is very different from that practised in Iran and Iraq.)

In late 2014, the Houthis marched down from the north and took over the capital, Sana’a – with the aid of army units still loyal to Saleh. After Hadi fled south to Aden in early 2015, the Houthis stormed the city and sent him into exile. One day after he turned up in Riyadh, a Saudi-led coalition that included the armies of the UAE, Qatar, Bahrain, Sudan and Egypt, with the support of the US, UK and France, began bombing Sana’a on behalf of the exiled Yemeni government.

The Houthis forced Hadi out, but they never managed to fully occupy Aden. Almost overnight, the city was filled with local men wielding guns along with their “commanders” – who gathered in schools, government buildings and squares. There was no structure; friends, activists, neighbours or relatives coalesced around a charismatic neighbourhood leader, financier or thug. Some were Salafis, some southern separatists, some al-Qaida, some just unemployed youth. Often there were no clear lines separating these groups. A commander could be both a southern separatist and a Salafi, and many of the young people who joined the jihadi groups did so not out of ideology but hatred of the Houthis and admiration for the jihadis’ discipline and plentiful supplies of weapons. They were separated by a thousand disagreements and united by one thing: fighting the Houthis.

Facebook Twitter Pinterest Tribesmen loyal to the Houthi rebels rally in the capital, Sana’a. Photograph: Hani Mohammed/AP

Not all the resistance factions were so disorganised. The Salafis, who set up their base in a football stadium, were dedicated, zealous and disciplined, and soon emerged as the most powerful element of the anti-Houthi resistance. “The Salafis had taken the decision to fight the Houthis even before they entered Aden,” one Salafi sheikh, who commanded his own force, told me a few months ago. “For us the war was to defend the Sunni nature of society. We fought the Houthis as a religious force. Everyone fought under our command: religious factions, southerners, street thugs and even al-Qaida. Sometimes the kids would stop fighting if they didn’t have internet and they couldn’t check their Facebook.” For sectarian and ideological reasons, the Salafis became the conduit of weapons and money sent by the Arab coalition, empowering them further.

The war had combined the secessionist zeal for south Yemen independence with Salafi and jihadi anti-Shia sectarianism. It was an explosive mix, and it swept over the city. Any northerner was a suspect, and hundreds were seized and detained in the stadium, accused of being Houthi agents. In December 2015, two mass graves were excavated nearby.

The Houthi occupation of Aden only lasted for four months. After they were driven out, the separatists of the Southern Movement had high hopes. For the first time since 1994 – when the north easily crushed the southern army to end a bid for secession – the city was free of any northern control. All the security forces were in the hands of southerners, and they had weapons and a strong ally, the UAE, which had taken control of the southern front.

With the Emiratis as their backers, the people of Aden believed their city would become the next Dubai, with electricity, water and jobs. The enthusiastic governor, a former general who had returned from London to help rebuild the city, told me companies would pour into the city; Aden would resume its former glory; its port, which had been stagnating before the war, would reclaim its status; and embassies would reopen. In the months after the Houthis’ departure in 2015, the Emiratis were celebrated as liberators, their flags sold on market stalls, and pictures of the rulers adorned street corners and weapons.

In the streets, the reality was different. “Liberated Aden” resembled other cities devastated by the civil wars that followed the Arab spring, with rusting, burned tanks and armoured vehicles perched on hills, overlooking a city of scarred streets and gutted buildings, toppled on top of one another like crumpled concrete wafers, and impoverished people left homeless and turned into refugee squatters in their own city. The defeated Houthi militia was replaced by dozens of others in a city without water, electricity or a sewage system. The war became the main employer, and the streets filled with fighters riding in the back of pickup trucks mounted with heavy machine guns. Commanders from the disparate, disunited resistance groups were demanding their share of the spoils from a broken and impoverished city.

The most powerful of those commanders, men like Ayman Askar, secured control of the ports, factories and any institution that generated an income, imposing their protection racket. The smaller commanders contented themselves with looting public and private property, especially if the latter belonged to northern owners.

‘When the battle [for Aden] was over we were left in chaos,” the Salafi sheikh told me. “The city was divided into sectors, and each force or militia was controlling a different part and clashing with the others.”

By the end of 2015, the war against the Houthis had become bogged down by the rivalries among the alliance members, the proliferation of militias controlling areas of the country, and the expansion of al-Qaida in the south. The dreams of the people of Aden that their poor city would flourish with the help of their rich Emirati brethren had subsided into resentment and frustrations. The Salafi sheikh was convinced that something had to be done.

Like many of the Yemeni commanders, the sheikh had become a regular visitor to the UAE, enjoying the hospitality of his new patrons and taking respite from the deteriorating situation in Aden. During one of his visits to Abu Dhabi, he said, he had met an elderly professor and adviser to Mohammad bin Zayed, the UAE crown prince and the head of its armed forces. The professor had coined a new phrase, “the Gulfication of the Arabs”, which was becoming popular among the ruling elite in Abu Dhabi. For the rest of the Arab world to succeed, according to the professor, they needed to follow the model of the Gulf monarchies – forgoing democracy and popular representation in return for providing financial prosperity and security. The Salafi sheikh was an instant convert.

One night in Abu Dhabi, not long after meeting the professor, the sheikh sat down in his lavish hotel room and began to write a long letter to his Emirati allies: a road map for saving the south of Yemen and the Saudi-led intervention. After praising Allah, the brave Emirati soldiers, and their wise commander Mohammed bin Zayed, he began to list the problems threatening the Emirati adventure in Yemen.

In a 16-point manifesto, titled the Road Map to Saving Aden, he called for the formation of a new security force composed of resistance fighters, the creation of a new intelligence service, and the implementation of “Gulfication” by banning political parties and, ideally, elections. “We had to defeat al-Qaida and use the south as an example of how to implement the new strategies of the Gulf,” he explained.

He warned that secessionist passions were gripping Aden, and suggested the UAE should take advantage of the moment by sponsoring a loyal faction of the separatists – in part to prevent another power, like Qatar or Iran, from co-opting the Southern Movement.

“Look, I work for the Emiratis as an adviser and I wanted them to succeed,” he told me. “Our fates are entwined: if they fail and decide to leave, it will be a disaster and Aden would be destroyed. I know that I need the Emiratis and I am dependent on them – and at the same time, I am not naive. I know they have their own project, and they have their own self-serving goals and agendas, but there is nothing wrong with cooperating with them.”

After he returned to Aden, the sheikh worked with an Emirati general to assemble and train a new security force loyal to them and capable of tackling the increasing jihadi threat. While publicly everyone was paying lip service to helping Yemeni government institutions and rebuilding a modern army, the reality was the Emiratis wanted their own client force that they could control with no intervention from President Hadi, who they saw as an obstacle – especially since he allied himself with the Emiratis’ enemy, al-Islah.

“The existing Yemeni army and police were corrupt and failed institutions. The Emiratis wanted a new force,” the sheikh said. “The plan was to train and equip a force of 3,000 men, but we ended up with a force of 13,000, so we divided them into four battalions.” The overall commander of the new force – which was dubbed “Security Belt” – and all the battalion commanders were southerners and Salafis, as were some of the fighters. The sheikh became one of the senior commanders.

Facebook Twitter Pinterest Security Belt forces undertake military training at their base in Aden. Photograph: Ghaith Abdul-Ahad/The Guardian

In time, the Emiratis formed half a dozen armies, dispersed across Aden and the south of Yemen. Their commanders function as independent warlords, with tanks, prisons and a force loyal to them personally. There is no central command connecting all these forces, and the government of Yemen has no control over them.

Instead, they work directly under the command of the reigning Emirati general, who appoints and dismisses them at will, and distributes his largesse according to their cooperation and effectiveness. Unlike the Yemeni government army units, with their inflated numbers and irregularly paid soldiers, the fighters in the Emirati-controlled forces are paid regularly and are better dressed and equipped, with an affinity for black ski-masks and extreme brutality. They detain, torture and kill with impunity.

I met one Security Belt commander at his base north of Aden, near a large checkpoint that separates the city from the neighbouring province of Lahej, where the jihadis had a very strong presence. When he first arrived, he said, al-Qaida fighters held positions less than 200 meters away. The entire province was controlled by them.

The commander explained how his forces had prevailed. “It was a tough fight,” he said. “For weeks we slept little more than two or three hours, patrolling the streets and snatching al-Qaida suspects … It was a simple formula. The leaders and the bad guys we killed. Those we deemed low-risk and reformable – collaborators or shop owners who dealt with them – we tortured and jailed, but then released after six months when they had signed a pledge. The rest of the population we keep in check through informants.”

In Yemen, according to a UN report published this year, all parties have been detaining suspects without trial, and torturing prisoners. The Houthis were disappearing writers, journalists and human rights activists even before the war started.

But no one can compete with the detentions, torture and forced disappearances by the Emirati-sponsored troops. An unprecedented campaign of terror followed the formation of these forces in 2016. At night men with balaclavas seized people from their beds. No one claims responsibility for these kidnappings. Although the action was launched ostensibly to fight al-Qaida, the targets expanded to include anyone who dared to oppose the UAE presence in Yemen.

In the summer I met with a human rights lawyer who works with Yemeni ministry of justice, compiling lists of detainees and collecting testimonies from them and their families. “After the battle for Aden we expected the Emiratis to form one army from the resistance – instead, they created a dozen forces and they are detaining anyone who opposes them,” she told me. “Pursuing al-Qaida became a pretext – anyone they don’t approve of is detained, and almost everyone detained is tortured, often hung from ceiling, many are sexually abused. The sad thing is that now southerners are torturing southerners with the blessing of the Emiratis – while the government of Yemen stands helpless and watches.”

She laid a thick pile of files in front of me – she believes there are at least 5,000 cases. “We have no power … we demand to visit prisons but they don’t answer,” she said. “Even if they are truly al-Qaida, they can’t be tortured like this. They are creating a timebomb of all those people who are tortured – putting the innocent with jihadis and children with old men in overcrowded rooms.”

Aden is gripped by fear, she told me. Life was easier during the war – you avoided the frontlines and cowered indoors. “We boiled potatoes and ate them with bread, but we felt safe. Now we live in fear.”

Some prisoners don’t know why they were detained. A young bespectacled university student, who loved reading history books and discussing them with his friends in a shisha bar, was seized last year by masked men, put in the back of a pickup truck, his head pushed to the floor, and taken into a windowless room where he was held for three weeks. He was interrogated a few times, but mostly he was left alone. Sometimes he thought his jailers had forgotten about him. Just before his release, an interrogator told him that it’s better not talk about “these books you read” in public, and he was sent home.

Many people were detained solely to pressure family members. In a brightly lit cafe next to a busy shopping centre – full of families, young women in long, black abayas and young boys in tight jeans and gravity-defying hairdos drinking mango and lime juice and eating burgers and fried chicken – I met Abdullah, a young university student. He drank his lime juice silently, revealing mangled skin on the side of his arm each time he lifted the glass.

In the middle of the night a year ago, masked men knocked at his door, told him he was needed for questioning, and assured his mother he would be back in the morning. They blindfolded him and bundled him on to the back of a pickup truck. When they took him off the truck, he realised he was in the notorious base of the commander of the Security Belt forces in Aden, Abu al-Yamama – a veteran officer in the long struggle for southern independence who has become a powerful Emirati proxy.

Abdullah was taken to a small cell and left there for a few hours. “Before dawn, four men entered the cell. They started beating me and asked me to admit that my brother was working with the jihadis. I swore that he wasn’t. He had a small shop fixing mobiles and computers. He didn’t even pray.”

Picking up a small water bottle from the table, he squeezed it a little. A few drops fell on to the white plastic table. “One of them brought a bottle like this one and started to sprinkle [something] on my back,” he told me. “I smelled petrol [just] before they lit it. I ran around the room hitting the walls and screaming so loudly that guards came and put out the fire.”

What he didn’t know then was that he was being filmed, and that his brother had already been detained, but had refused to confess. “When they showed the film to my brother, he signed a confession immediately.”

Abdullah was taken to a clinic and after an intervention from his powerful tribe, six months later, he was out. He lifted the edge of his T-shirt to show me his back, where the flesh was mangled and scarred. His brother has yet to be charged or released.

When I asked the Salafi sheikh about these abuses, he squinted, looked into the middle distance and said they were committed by the UAE’s local partners. “The policy in targeting and detaining al-Qaida suspects is internationally acceptable, and the Emiratis are partners with the US on that,” he said. “To target and disappear an al-Qaida suspect – that’s fine. But to put a man in a jail for a year, torturing him just because his son is accused of joining al-Qaida, that’s a problem.”

Abu al-Yamama is a name that makes men shiver in Aden. He is very proud of his elite units – trained by the Emirati special forces – who are, more than anyone else, associated with the worst of the atrocities. I sat next to him one morning on his base while he watched his troops practising a raid: a group of them, all dressed in black, stormed an empty room and dragged out one of their own fighters, shoving him hard on the concrete floor before bundling him on to the back of a pickup truck and speeding away. They repeated the same exercise several times.

Later, in his office, Yamama dismissed all the claims of arbitrary detention and torture as a plot by the Muslim Brotherhood to harm the reputation of his forces. “What do they expect me to do to the people roaming the streets with explosive belts?” he asked. “Send them some roses and invite them politely to come visit me?”

In the south, the old dream of independence has never died. Like all residents of cities cursed by the disparity between a glorious history and a wretched present, the people of Aden are condemned to yearn for an imagined past. This yearning is a form of narcotic, and often harmless, until it is fused with nationalist or sectarian myths, when the mixture becomes volatile and explosive.

In the years since unification, the southerners saw their secular socialist state annexed by the more powerful north; they saw their factories dismantled, their officers fired from government posts, their lands taken over, and their education and health systems collapse. Their once poor-but-functional state was replaced with a corrupt, nepotistic tribal regime; what was supposed to be a partnership with the north was simply a takeover.

For more than a decade – well before the uprisings of the Arab spring – the fervent and passionate people of south Yemen have romantically, even naively, called for the resurrection of their old state. They chanted and demonstrated peacefully in the streets of Aden, and in villages in the mountains and the deserts, and they were met by brutality and violence. The security forces under Saleh, and then Hadi – a southerner who fled to the north in the 1980s and then led the northern army that crushed the last attempt at southern independence in 1994 – fired teargas and live ammunition at peaceful demonstrators, and used detentions, torture and sometimes even extrajudicial killings to suppress the Southern Movement. Their cause was largely ignored – by the world and by their neighbours – until the Houthis invaded the south, and then everything changed.

“Now we have an army, and we control the south, and we have a regional ally who stands by us,” I was told, proudly, by one of the leaders of the Southern Transitional Council – the primary separatist organising body and the most prominent political power in the south, with heavy backing from the UAE. (The creation of the STC was one of the 16 points of the “road map” outlined by the Salafi sheikh, who is one of its members.)

Facebook Twitter Pinterest Pro-Yemeni government forces guarding a frontline in the south of the country. Photograph: Ghaith Abdul-Ahad/The Guardian

“We have never been so strong in the south,” the STC leader said. “People say we are under the control of the Emiratis, as if they can move us with a remote control. But the Emirates is not a charity. Of course they have interests – securing the coast, getting rid of al-Qaida, and having a friendly state here in south Yemen. The Emiratis needed a partner, and when they saw the failure of Hadi’s government, they had to take action.”

But the dream of southern independence is still shrouded in myth. In their rhapsodising about the old south, many separatists forget to speak of the hunger and the repression of those years, and gloss too easily over a history of conflict and division. The heroes of independence, who drove the British out in the 1960s – and then abolished the tribal system, emancipated women, eradicated illiteracy and stretched the reach of the bureaucracy beyond the limits of British Aden into the furthest village in the desert – ended up feuding like all revolutionaries do.

Their disagreements over socialist theory and the shape of the state inevitably became personal and violent, culminating in the south’s own 10-day civil war in 1986 – whose losers, Hadi among them, were exiled to the north before returning victorious when the north easily vanquished the southern army in 1994. Now those who lost in 1994 are siding with the Emiratis, while Hadi and his allies are against them.

Of course, history is not on a loop – but just as the Americans, with extreme ignorance, set the stage for a brutal civil war in Iraq by allying themselves with one side, so have the Emiratis created the conditions for the resumption of strife and civil war.

“I don’t want the [independent] south anymore,” one young activist told me. “For many years, my friends and I dreamed of the south, but if they are so divided now, what will happen when they become a state? They will be killing one another in the street as they did before.”

This summer in Aden, huge billboards hung over the streets. They had pictures of the Emirati crown prince, Mohammed bin Zayed, along with Hadi and a handful of lesser commanders – some alive, some dead. On the walls there was stencilled pro-UAE graffiti, and posters emblazoned with their flags. But over the summer, “Down with Emirati occupation” slogans started to appear.

The uprisings of the Arab spring, and the violent chaos that followed, created a shift in the power dynamics of the Arab world. Not only did the Gulf monarchies loudly proclaim themselves the new symbols of stability in a region torn by civil war, they also seized the moment to project their new power by intervening in their neighbours’ conflicts, financing and arming militias in Syria, Libya and Yemen, and backing a military coup in Egypt.

Under the hawkish Zayed, the UAE has embraced a much more assertive foreign policy, intended to establish the Emirates as a regional power. In Yemen, the UAE has three central missions that are separate from its support for the Saudi coalition. First, to crush political Islam in any form. Second, to control the strategically valuable Red Sea coastline – across a narrow strait from the Horn of Africa, where the UAE has already established military bases in Djibouti and Eritrea. And third, to develop and strengthen its own special forces, who train and oversee local proxies like the Security Belt troops.

The increasingly visible pursuit of these geopolitical imperatives has not necessarily impressed their ostensible allies in Yemen. In Aden this summer, criticism of the UAE was spreading, especially among the poor, who had thought the presence of their very rich neighbours would make their lives better. Instead, the electricity supply had got worse, preventable diseases were spreading, and the collapse of the Yemeni riyal was making them even poorer.

In September, demonstrations erupted in Aden and the rest of the south over the state of the economy. By now, all hope of new development had faded, and enthusiasm for the separatist STC has fizzled into infighting and rivalries. Even among the Emiratis’ staunchest allies, the Salafis, there was growing resentment at being used as cannon fodder in someone else’s war.

As one Salafi resistance commander who stopped fighting alongside the Emiratis told me angrily: “Why are we sending our best men to die at the front – and bombing civilians who are trapped between us and the Houthis – just because they want to control the coast?”

In a small hotel room in one of the poorer parts of Aden, I sat with three Southern Movement leaders, who had all fought in the resistance, and all previously considered themselves friends of the Emiratis, from whom they had received weapons, money and trucks. But all of them said that in the past year they had been targeted for arrest or assassination by the Security Belt forces. “A war with them is only a matter of time,” one said.

All three have now joined the Hadi camp. I asked one of the men – who spent years campaigning for southern independence – why he was suddenly plotting against the Emiratis and the STC. “We wanted a south based on state institutions, and not militias,” he replied. “What we have now is a state of chaos where masked gunmen kill and detain at will. This is not the south that I have been campaigning for. Either the Emiratis take the south and declare it their colony, or they must respect the people and the president.”

On my last visit to the Salafi sheikh in Aden, I found him despondent. “The south has been ruled by the southerners for the past three years, and yet it has been a failure,” he said. He insisted that the Emiratis must stay, because if they leave, “Aden can easily fall again, and all these units will be fighting one another. We need them to stay. At the same time, I am frustrated by the mistakes they make. I understand that they are still learning, because they don’t have the experience as an imperial nation, but then they behave with the arrogance of an imperial nation.”

He concluded: “I know two years is not a long time in the life of a nation trying to build an empire, but it is a very short time to turn your friends into your enemies.”

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