When Staffan de Mistura became UN special envoy, his past successes brought hope for peace. A year later, with no solution in sight, he faces heavy criticism. Has his innovative diplomacy failed or is it simply mission impossible?

In July 2014, Staffan de Mistura, a 68-year old Italian-Swedish diplomat, was enjoying a peaceful semi-retirement on the isle of Capri when he received a telephone call from his former boss, the United Nations secretary general, Ban Ki-moon, offering him what might be the world’s most difficult job. De Mistura had worked under Ban as the chief of the UN missions to Afghanistan and Iraq, and he was now being asked to take up a role as the UN’s special envoy for Syria – charged with finding a peaceful resolution to one of the bloodiest and most complex wars of our time.

De Mistura hesitated. Following a stint as a deputy foreign minister in the Italian government, he had recently become the director of Villa San Michele, a Swedish cultural foundation on Capri, and he was considering setting up a Mediterranean policy thinktank. After 42 years of humanitarian work and 19 overseas missions, largely in conflict zones, he had promised his fiancee and two children (from a previous marriage) a “more normal life”.

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He also had a political motive for resisting the role. The first two UN special envoys to Syria, the former secretary general Kofi Annan, and the veteran diplomat Lakhdar Brahimi, were colossal statesmen, and yet both had been unable to cease the killing. The UN security council remained deeply divided – with China and Russia backing the government led by Bashar al-Assad, and the US, UK and France broadly supporting a ragged coalition of opposition groups, led by the Syrian National Coalition. Neither the Assad regime nor the fractious opposition demonstrated the slightest willingness to compromise or even negotiate. Both Annan and Brahimi eventually resigned in frustration and disgust.

After his successes in Afghanistan and Iraq – where US President Barack Obama had singled him out for praise – De Mistura had to wonder whether there was any good reason to put his reputation on the line for a job that was destined to end in failure: “Mission Impossible”, as one of his closest friends called it.

The job of the UN special envoy for Syria is a uniquely onerous one. As the nominal representative of the “international community”, in the form of the UN, the envoy’s fundamental task is to bring warring parties to the negotiating table to begin some sort of conversation. But in the case of Syria, where at least half a dozen nations are involved, that requires the participation of not only the major regional actors – the Saudis, Turkish, Jordanians, Qataris and Iranians – but also various world powers, including Russia, China and the United States. (Because no country in the region is considered to be impartial in the Syrian conflict, the office of the special envoy is now located in Geneva.)

As he contemplated Ban’s offer later that night in July, De Mistura could not sleep. “I felt guilty,” he told me when we first met in August. He had done humanitarian work for decades in some of the world’s worst war zones, driven by an impulse he likes to call “constructive outrage”. De Mistura was inclined to say no – but he kept thinking back to Ban’s parting words. “He shared with me, very wisely, the current situation in Syria,” De Mistura told me. “How many dead, how many refugees, the level of horrors.” A few hours later, at 3am, he called Ban and accepted the job. Then he returned to bed to tell his fiancee “She was not surprised,” he said.

De Mistura has developed a reputation as an innovative and creative diplomat, with a particularly strong sympathy for the struggles of civilians and refugees. (His own father was left stateless and without a passport after the second world war: “I understood, at 10 years old, the strongest pain for a political refugee is lack of dignity,” De Mistura said.) Colleagues and friends regaled me with tales of his talent for improvisation: how he convinced a commercial airline to fly food into a starving Kabul in 1989; how he had World Food Programme camels carrying vaccines in Sudan painted blue so they could be spotted by helicopters and protected against theft; how he used smugglers to break the siege of Sarajevo and bring meals and blankets to the city’s desperate inhabitants. He talks passionately about how the denial of access to water has been used as a weapon of war, “especially in a hot Syrian summer”. He has also repeatedly confronted Assad over the use of barrel bombs – improvised explosives thrown out of aeroplanes with minimal precision – in civilian areas.

But De Mistura’s talents have been of little use in Syria: according to a senior UN official who works with him, the fundamental obstacle to any progress towards negotiations is that none of the warring parties – those fighting on the ground, as well as the regional and world powers conducting a proxy war – has any interest in stopping the conflict. “They both thought they could win, and when mediators have tried to take an impartial stance, they cry foul,” the UN official told me. “The same thing happened with Annan and Brahimi.”

Among the greatest difficulties for both De Mistura and his predecessors has been merely sustaining the attention of the rest of the world. Brahimi resigned, he said, “because I was getting nowhere and it was the only way for me to protest the total inattention of the international community and the region to the situation in Syria”. Today, more than a year after resigning, Brahimi told me in Paris, “There are still viable solutions – there is always a solution. But the real question is: Is there enough political will and clout?” If the parties wanted to stop fighting, in other words, they could negotiate a resolution. But they do not want to stop fighting.

There are still viable solutions, there is always a solution. The question is: Is there enough political will and clout? Lakhdar Brahimi

De Mistura has tried to pursue a more creative sort of diplomacy – less bound to the rigid UN framework in which Annan and Brahimi preferred to function – in line with his reputation, in the words of one friend, as a man who “loves gimmicks”. Last Sunday, De Mistura arrived in New York after clocking up 26,000 miles of air travel in two weeks, meeting with leaders in Syria, Jordan, Saudi Arabia, China and Iran, in a desperate attempt to put the political process back on track. This week, he briefed the UN security council once again on options for action, which many hope have been opened further by the signing of the US-Iran nuclear deal. The Iranians may be the only force capable of persuading Assad to step aside or negotiate in good faith, but Washington is nervous that aggressive diplomacy might affect the approval of the nuclear deal in Congress later this year. In the meantime, Syria is dying.

“He’s trying to explore all options,” said Michael Keating, a friend of 30 years who served as De Mistura’s deputy in Afghanistan. “That’s the way he is.”

As the third negotiator to attempt to forge an end to the fighting, De Mistura came into the job with energy and ambition – he once called himself a “chronic optimist” – but it has been a struggle to retain hope. “Over time, it’s become a proxy conflict, where many, including the Syrian government, are ready to fight to the last Syrian in order to force the world to recognise that their position is the right one,” he told me before leaving for the UN earlier this month. “This is the most cynical war I have ever encountered.”

* * *

De Mistura has now been in the job for a year. Inside, Syria is burning, with Turkey, Iran, Saudi and Qatar hovering on the sidelines waiting to pick its carcass clean; its borders flooded with four million refugees; 230,000 dead, and chlorine attacks and barrel bombs continuing to drop on civilians. It is a grisly war, the worst I have seen after many years of reporting conflict. The main actors – the Syrian government and the opposition Syrian National Coalition, are not ready to stop fighting; nor have they been willing, thus far, to negotiate in good faith. The rise of Isis has created an even greater obstacle to negotiations, allowing Assad to position himself as part of an anti-Isis coalition – and raising the painful fact that many Syrians would rather align themselves with Assad’s regime if the alternative is a violent radical jihadist group.

Facebook Twitter Pinterest UN special envoy Steffan di Mistura meets President Assad in Damascus in November 2014. Photograph: AP

From the beginning, De Mistura knew he was, in a sense, staring into an abyss. When we first met in Brussels, where he lives with his fiancee, a few weeks after he took the job, De Mistura spoke of the catastrophic impact of the war on Syria’s civilians. He referred back to the frustrations he had faced in his own past assignments in Sudan and Bosnia. De Mistura has an aristocratic glamour that is rare in the UN: he speaks seven languages, bows and kisses hands, wears finely cut suits and pince-nez spectacles, and has been known to carry a silver pepper mill on his field postings. He is an attentive listener, and the sincerity of his concern for the Syrian people is evident.

But in the past few months, De Mistura has come under attack from all sides for failing to make progress towards ending the war. He has been criticised for not doing enough to engage the Syrian opposition, for failing to make proposed ceasefires stick, for focusing on the political process to the exclusion of reducing violence against civilians, and harshest of all, for staffing his own team with longterm associates – the word “cronyism” is often heard – rather than experts with experience in the region. Kenneth Roth, the director of Human Rights Watch, has accused De Mistura of “not getting the big picture” and chasing quixotic local ceasefire efforts. “The international community has been one-dimensionally focused on peace talks that are going nowhere at the expense of stopping the slaughter of civilians,” Roth told me. “De Mistura is trying to get people who are shooting rifles at one another to stop, but that is not what is killing civilians.”

De Mistura’s critics argue, in essence, that he has done even worse at his impossible job than he should have – a difficult accusation to judge. “Whether you’re a good negotiator or a bad negotiator, if the situation is not ripe, there is nothing you can do,” a senior American diplomat told me. “You can take advantage of the situation on the ground, which is how the Bosnian war ended. But if you are the UN, you can’t shape the situation. You can be nimble in responding. But that requires experts so you can understand the dynamics. You should have a plan of great detail in your pocket when the time is ripe.”

De Mistura’s critics argue, in essence, that he has done even worse at his impossible job than he should have

De Mistura is aware of this. “You can’t shape the situation but you can shake it,” he insisted. “You can come up with initiatives. Even if they are not necessarily the most effective ones.” He takes most of the criticism with equanimity, though he was hurt by a report in the New York Times in May that implied he was a lightweight (“more widely known for his dapper style than for any diplomatic coups”) and reported that he had spent too much time, on an earlier posting in Lebanon, sunbathing rather than peacemaking. (“It was his first family posting,” said his friend Andrew Gilmour, the political director in the secretary general’s office – who has worked with him for 25 years in conflict zones – in De Mistura’s defence.)

The accusations of cronyism particularly stung. De Mistura had initially thought it best to hire staff who had served him well in the past – and whose strongest quality was fierce allegiance to him – but this approach may have backfired. “Cronyism is getting someone a job in Geneva or New York,” De Mistura argued – not on the frontline of a war. But the work of his team has come under harsh scrutiny. In March of this year, De Mistura dispatched an insufficiently experienced team to Turkey to meet with Syrian opposition figures. Most of the Syrians refused to attend, and those who did were unimpressed. “It was embarrassing,” said one UN adviser who witnessed the fallout. The report they later issued on the meetings was regarded as weak and insubstantial, and other leaked memos from the office have been ridiculed inside and outside the UN for their poor analysis and lack of intellectual heft.

“A team full of cronies is a disaster,” the senior US diplomat said. “You need real experts who can pull out the nuances. You need people who know the dynamics among the groups and within the group.” Mouin Rabbani, an experienced Middle East analyst who served as De Mistura’s political director before resigning earlier this year, argued that the team was composed of “individuals whose qualification is personal loyalty and a record of service to him”.

“I am in no way making the claim that the Syria crisis was ripe for a solution and the UN blew it by appointing a special envoy who was out of his depth,” Rabbani continued. “Indeed, his predecessors also failed. But the UN failed Syria and its people by appointing an envoy who lacked the capacity to either exploit or create opportunities, however limited, for conflict mitigation.”

But it remains the case, as even De Mistura’s critics acknowledge, that neither side has any appetite for negotiation. In May of this year, he announced a round of one-on-one “low-key” talks with dozens of parties in Geneva in an attempt to find any areas where discussion might move forward – but even that initiative has been troubled by the refusal of many opposition groups to participate, in part due to their displeasure that Iran, the main backer of the Syrian regime, would be among those speaking to De Mistura.

The following month, De Mistura went to Damascus to meet with the Syrian government, determined to push Assad once again regarding the use of barrel bombs. As he was waiting for his meetings to begin, bleak news arrived from Aleppo, where heavy shelling near a mosque had killed dozens of people and wounded nearly a hundred, many of them children. This time, the perpetrators were not the Syrian regime but armed opposition forces.

After meeting Walid al-Moallem, the Syrian foreign minister – and briefing him on the consultations in Geneva with various Syrian civil society groups in May and June – De Mistura sat with Assad for an hour. He bluntly demanded an explanation for the Syrian president’s decision to continue dropping crude bombs on his own people.

What was Assad’s response? “That I cannot discuss,” De Mistura said. But it was clear that the Syrian leader was not happy with the envoy’s forthright approach. A week later, De Mistura was back at his office in Geneva, when news arrived of further barrel bombings by the regime. He issued strong statements rebuking both sides – but knew very well that statements alone cannot do much good.

“Sometimes,” De Mistura admitted, looking out over the lake adjacent to his offices, “I feel like a doctor who is trying to keep a patient alive, but only able to relieve the pain.”

* * *

By the time Kofi Annan, the first UN special envoy, convened talks in Geneva at the end of 2012, the Syrian war had already been raging for more than a year. In the months after peaceful protests against Bashar al-Assad were met with armed force in early 2011, nearly the entire country had become a battlefield. One by one, cities were besieged, provincial areas starved, and in some cases, villages annihilated. By the summer of 2012, only Damascus – still under Assad’s control – remained unscarred by war; civilians in Homs, Aleppo, Hama and other cities were being pummelled, and horrendous abuses of human rights were happening on a daily basis.

Thousands of civilians were being slaughtered, and even more were incarcerated and tortured. And the atrocities were not just coming from Assad’s side: as many in the opposition Free Syrian Army grew disillusioned and defected to either Jabhat al-Nusra – the al-Qaida franchise in Syria – or Isis, reports of war crimes abounded. Both sides used rape as a tool of war – in jails and at checkpoints. Massacres in Daraya, near Damascus, in Bayda and Baniyas, in western Syria, and Houla, near Homs, saw hundreds of civilians slaughtered by the Syrian army or regime-backed militias, leaving villages razed and piles of corpses in mass graves.

Attempts to reduce the bloodshed began early on: the UN did important work in Houla after the massacre there in May 2012. But as I watched them try to operate in Syria, it became clear how difficult it was to manoeuvre: UN monitors in Damascus were not allowed to leave their own hotels because they were getting shot at; human rights officers working for the UN could not even get into the country, as the regime denied their visa applications. From the start, there were grave frustrations and overt obstructions.

Facebook Twitter Pinterest Kurdish refugees get on a bus in Turkey having fled the civil war in Syria. Photograph: Bulent Kilic/AFP/Getty Images

I left Damascus in June 2012 to fly to Switzerland to cover the Geneva talks convened by Annan – the first attempt to end the war, which involved representatives of the five permanent members of the UN security council, along with Turkey and three Arab states – but not Iran, Saudi Arabia, Syria, or the Syrian opposition. They laid out the so-called Geneva Communique, which outlined a path for ending the conflict: a ceasefire of all parties; the establishment of a transitional governing body; a constitutional review subject to public approval; and free and fair elections after such a review. The Americans, British and French clearly felt the terms of the communique implied Assad’s exit, while the Russians maintained it would prevent any outside solution being imposed on Syria. But most observers now feel the communique badly needs to be updated, since the central issue has become whether Assad stays or goes.

Annan resigned a month after the Geneva talks, to be replaced by Brahimi, who struggled to bring the warring parties together for another conference in early 2014. The so-called “Geneva II” conference (which actually began in Montreaux) was initially viewed as little more than a photo opportunity. The mood was grim and hopeless, and the talks were a shambles. Iran was briefly invited, only to have its invitation revoked by Ban Ki-moon after it refused to support the terms of the Geneva Communique – a move that infuriated the Russians. John Kerry, the US secretary of state, declared in his opening remarks that Assad would have to step down, sparking the fury of the Syrian government.

As reporters, myself included, watched from the sidelines, the talks descended into farce. Because the parties would not talk to each other, all communications had to pass through Brahimi. One senior diplomat recalled, with gallows humour, an exchange over the status of opposition prisoners. The rebels asked Brahimi, who passed the question on to the Syrians, and then took their response back to the opposition. “What prisoners?” came the reply from the Syrian regime. “We have no prisoners. We only have terrorists and suicide bombers.”

“What about the women and children?” the opposition asked. Brahimi, persisting with the charade, took this question to the Syrians, who replied, “We have no women and children. We only have potential suicide bombers.”

The parties could not even agree on how to negotiate; the government demanded that all their priorities be discussed first. The main impasse was the role of Assad himself. The opposition refused to consider a scenario with him; the government refused to see a new Syria without him. The other roadblock was the regime’s definition of terrorism – which included all armed opposition – and therefore all parties with whom they could potentially negotiate.

Brahimi, an impressively large and elegant man who had previously negotiated the end of the civil war in Lebanon, looked slumped and diminutive when he came out to face the press in Montreux before the second part of the talks began.

Although both sets of talks were seen as useless, De Mistura has not ruled out attempting a third Geneva conference; his “consultations” in Geneva this May were, in a sense, intended to soften up the parties with discussions of their intentions for Syria’s future, and to coax them back to the table one more time. But he may not have a vision for how this might happen – especially while the multiple sides, and their foreign backers, Iran and Saudi Arabia, show no signs of giving in. Meanwhile, Dr Khaled al-Khoja, the president of the opposition Syrian National Coalition, argued that De Mistura’s efforts should be concentrated on protecting civilians rather than high-level political negotiations with little hope of success. “What we are demanding is protection from the air, from the barrel bombs,” he told me. “This is the duty of the international community. We are talking about safe zones, so we can defend ourselves.”

* * *

At the beginning of the war, one could hire a trusted driver and take the road from Turkey to Aleppo, about an hour through a wasteland of blackened cars, checkpoints, and shells of villages. Aleppo was once the glory of Syria – a Silk Road city that was home to Christians, Sunnis, Shia and Greek Orthodox people. In the early part of this century, the city even became a trendy tourist destination: foreigners bought homes in the old city; there were direct flights from Paris and London. Art collectors and designers, such as Christian Louboutin, a friend of the first lady Asma al-Assad, hosted parties in their elegant homes there. For a brief moment, it looked likely to become the new Marrakesh.

But when the war came, Aleppo was hit hard in bitter fighting between the Free Syrian Army and government troops. Soon, there were shortages of petrol, water, bread, electricity, food and medical supplies. Aleppo was once home to Syria’s best cancer hospital; now anyone there with the misfortune to contract a chronic illness is almost certain to die. One freezing December day, I watched an infant slowly die as a team of doctors – all residents, not yet fully fledged physicians – desperately worked to save her. She died because of a respiratory illness, an entirely curable disease, because her parents could not get to the hospital as the bombing was so bad.

In the autumn of 2014, early in his tenure, De Mistura came to believe Aleppo could be the key to ending the war. He believed that a ceasefire there would have immense symbolic power, rather like a Syrian Sarajevo.

De Mistura believed that a ceasefire in Aleppo would have immense symbolic power, rather like a Syrian Sarajevo

He was advised to choose a less difficult place – the city had a fractured opposition, and Isis and government forces were still wreaking havoc – but De Mistura was firm that an iconic image was needed. “It was an opportunity to dramatise the need to protect civilians everywhere else,” he said.

His plan was to bring small, local ceasefires to Aleppo neighbourhoods one by one, then link them up and eventually link up other cities and areas. There had been other local truces with some success – in parts of Homs, in Barzah, a neighbourhood in northeastern Damascus, and in Ras-al-Ain, a town on the Turkish border.

The idea for a local ceasefire was inspired by a former reporter and analyst, an Arabist named Nir Rosen, who has worked in nearly every conflict zone in the Middle East, and had extensive contacts on both sides of the Syrian conflict – including the on-the-ground experience inside the country that many on de Mistura’s team lacked. Working for a Geneva-based mediation group called Humanitarian Dialogue, Rosen had drafted a paper proposing a series of “freezes”, or local ceasefires, that would halt fighting and allow humanitarian aid to come in, creating safe zones for civilians. If the freezes could be shown to work in Aleppo, they could be extended to other parts of the country.

Critics of Rosen’s “freeze” proposal argued that it would result in terms favourable to the regime – but in any case, De Mistura’s proposal, which was drafted by members of his staff and presented to the security council in October 2014, was far less detailed. Some observers sympathetic to the plan argued that a more robust proposal like Rosen’s would have met with better results, but the idea was met with scepticism by the council.

Throughout the autumn and early winter, De Mistura’s team tried to reach out to various leaders in the opposition, who shunned them on the grounds that the special envoy’s office was too close to Assad. Brahimi and Annan had faced a similar problem. “The opposition basically did not want the UN to talk to the regime, full stop, because they see themselves as the legitimate leader of the Syrian people,” one UN official told me. “But the UN is obliged to talk to the official Syrian government in Damascus.”

In December, De Mistura mentioned the Aleppo freeze proposal publicly before he had discussed it with Assad’s government – who apparently learned of the idea from news reports. When he returned to Damascus in February of this year for talks with Assad and his ministers, they reacted aggressively. “Why are you choosing a place where we are winning?” they asked De Mistura. “You should have at least consulted us.”

On that same trip, De Mistura was photographed attending a party in Damascus to celebrate the anniversary of the Iranian revolution – which might not have been an issue, but for the fact that Syrian fighters backed by Iran were maiming and killing nearby in the rebel-held Damascus suburbs. The party picture quickly went viral, after it was tweeted by an influential Syria analyst, though De Mistura still maintains he was obliged to attend. “If any member state has a national day – which it was – and I happened to be there, I have to go,” he told me.

De Mistura further infuriated the opposition with an offhand remark at a press conference in Vienna a few days later. After discussing his freeze proposal at the end of a meeting with the Austrian foreign minister, he argued that it could save thousands of lives, but suggested that it would be necessary for the opposition to consider the possibility that Assad would remain in the political framework. The remark, he said later, was intended “to drag Assad into the circle of the solution – implicating him in the beginning of a solution”. It was not meant, he maintained, as a literal endorsement of Assad’s position.

Unfortunately, it came on the same day that the regime fired missiles and barrel bombs on Douma, near Damascus, and the suggestion provoked stunned outrage from the Syrian opposition, as well as the Americans and the French, who had insisted from the beginning that the war could only end with Assad’s removal. That was the final straw for the opposition, who declared it would boycott all meetings with De Mistura and his team.

The freeze plan limped on until February, when De Mistura appeared before the security council in New York to brief it on the possibility that Assad would agree to halt airstrikes on Aleppo. As he prepared for the briefing, however, all hell was breaking loose in the city: the Syrian government launched a military offensive to encircle the last enclaves of resistance in Aleppo and cut off their supply lines – arguing that since they had not yet fully signed on to any ceasefire, they could continue fighting. De Mistura felt he had been betrayed, and emerged from the briefing in New York looking furious.

Meanwhile, back in Geneva, De Mistura’s political director, Mouin Rabbani, had resigned in anger, and was giving blunt interviews accusing the special envoy and his team of incompetence. “It was amateur hour of the most cringeworthy kind, akin to sending a newborn baby into the ring to seize the heavyweight title from Muhammad Ali,” Rabbani told me. “De Mistura quickly lost the trust of the relevant players. Rather than play it straight, he had a tendency to tell those he meets what they want to hear, and worry about the consequences later.”

Rabbani’s criticism further damaged morale in an already weak office – and De Mistura seemed to be genuinely unaware of the disharmony surrounding his mission until negative press began to appear this spring. But he has acted quickly to make changes in the months since, hiring a new political director with expertise in constitutional law, and redoubling his efforts to mend relations with Syrian opposition leaders. As Dr Najib Ghadbian, the opposition envoy to the US and UN, told me in New York: “It is true that we were not talking to them, but we are now – we have to work with them.”

De Mistura, for his part, still believes it is possible to reach a political solution – before the international community can deal with Isis, he argues, there must be some template for a negotiated end to the conflict.

* * *

There is no formula for ending a war. History may suggest patterns of possibility, while diplomats have their own creative methods for breaking deadlocks at the negotiating table. But after watching De Mistura for the better part of a year, it is hard to see how anyone could bring the parties close enough for even the most brilliant diplomat to secure an agreement. His desire to end civilian suffering is powerful, but he has no sway over what happens on the ground – where the combatants show no signs of halting the slaughter.

The most extraordinary diplomatic negotiation of recent times may have been the talks to end the war in Bosnia – a conflict that the Syrian war is increasingly coming to resemble. The American envoy Richard Holbrooke negotiated a peace over 21 days of talks on an airbase in Dayton, Ohio, after deploying every possible means to force the parties into dialogue – from passing messages on napkins between the antagonists over lunch to forcing his colleagues to stay up all night drinking with the Serbian leader Slobodan Milosevic. Like De Mistura, Holbrooke seemed to be facing the impossible – and on the final evening of the talks, faced with what looked like certain failure, he gave all three sides a draft of the statement he planned to issue the next morning, declaring that the negotiations had failed. It was bullying, but brilliant bullying, and it forced the talks to a successful conclusion.

Facebook Twitter Pinterest Eastern Damascus in May after an airstrike allegedly by the Assad regime. Photograph: Reuters

De Mistura brightened when I mentioned Holbrooke over dinner one night in Geneva, shortly before he departed again for Damascus in June. “Dayton ended the killing,” he said. “And that is what we are trying to do. End the killing.” But Holbrooke – who represented the most powerful country on Earth rather than the UN – had crucial advantages over De Mistura, not least the fact that the combatants had already agreed to negotiations. It’s not clear that a similar endgame for Syria yet exists.

“There is a plan,” De Mistura said with confidence in New York earlier this month. He would not elaborate at the time, but in a briefing to the security council on 29 July, 2015, he proposed a series of “working groups” that would convene the Syrians themselves to discuss four separate subjects – including civilian safety, political issues, and military issues – in the absence of any agreement about a transitional government that might displace Assad. “They can start working right away,” De Mistura told me this week. “We don’t have to wait for the Iran deal to be closed.” The working groups, he continued, will take place in Geneva, chaired by the UN. “We will apply the same principles as during the Geneva consultations, those who refuse to come are welcome to join at any time. If they don’t want to talk to each other face to face, we will put them in separate rooms. We all know that people like Russia, the US and Saudi Arabia are talking to each other. A lot of these discussions are moving in a certain direction. We have to allow these talks to take place. In the mean time, what we do is we keep on pushing.”

Other diplomats have their ideas. Jonathan Powell, the veteran mediator who was Tony Blair’s chief of staff at the time of the Good Friday agreement in Northern Ireland, argues that any resolution must involve Iran. The US-Iran nuclear deal “allows a solution to the Assad problem to be much more conceivable,” Powell said, meaning the Iranians would put pressure on Assad to go. “The key is to appeal to the interest of the Iranians.”

Carne Ross, the former British diplomat who now advises the Syrian opposition coalition, has a competing vision – a more muscular and less theoretical approach, which would involve no-fly zones to protect civilians, as well as economic sanctions. Ross argues that the conflict has reached such an impasse that no party – least of all Assad – will sign up to any peace deal that actually demands a transition from dictatorship to democracy. “Economic sanctions are what eventually forced Milosevic to come to Dayton in 1995,” Ross said. “I think De Mistura needs to say this to the security council and demand their support for such a threat,” he added. “Peace envoys need to say clearly the tools they need to make peace. Parties don’t stop fighting until they have to.”

De Mistura’s greatest concern is that Syria will fall away from the international agenda, as people grow weary of watching the bloodshed and come to believe that this is a forever war, a lost cause. But with each month he struggles to devise new approaches, observers could be forgiven for concluding this may indeed be the case.

“It becomes almost embarrassing,” he said. The Aleppo freeze proposal, he argued, at least “kept Aleppo on the agenda – it kept people attentive about the outcome. The biggest danger is for Syria to be put on the back burner.” He remains undaunted by his critics. “The worst criticism is that you are doing nothing,” he said. “It is your own self-criticism. Your own voice.”

“If history teaches us one thing,” Richard Holbrooke once noted, “it is that history is unpredictable. There will be other Bosnias in our lives … they will originate in distant and ill-understood places, explode with little warning, and present the rest of the world with difficult choices.” Two decades after that war, the Syrian conflict has presented the world with an even more intractable conflict, and even more difficult choices. The US has set the stage by keeping a distance – an approach that has had deep repercussions. Europe has followed its lead. At present it is not easy to imagine what a peace in Syria might look like. Khaled al-Khoja, the president of the Syrian National Coalition, described to me what he called a “New Syria” in the aftermath of the war. “It will be united under one flag,” he said from his office in Istanbul. “There will be one overarching Syrian identity. But there will also be sub‑identities, collective rights, individual freedoms.”

Before that point, of course, the war will have to stop. And then, the Syrian people will have to reckon with the crimes against humanity that have been committed, by all sides, over the past five years. Any chance for reconciliation after this horrific war, therefore, will hinge on how it is brought to an end. In that sense, De Mistura’s task is even more daunting than mere diplomacy: he is tasked with trying to forge forgiveness for the unforgivable.

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