A thundercloud, heavy and dark gray. That is what it looks like from a distance. But the closer you get to Mosul from the south, the bigger and darker this cloud becomes. Instead of floating in the sky, it grows out of the ground, ultimately becoming a towering, opaque wall that swallowing entire villages, making them disappear into the darkness.
Driving to Mosul is a drive into the apocalypse. Or at least that's what it feels like, with the gigantic clouds of smoke coming from burning oil wells, reservoirs and ditches -- laid out by Islamic State over the last two years and now set alight one after the other. Although it would normally be a sunny midday in fall, the military jeeps coming from the other direction have their lights on.
The dark curtain is meant to keep the attackers' jets and helicopters at bay; the smoke irritates the throat and causes headaches. An armada of over 30,000 soldiers and fighters from at least a half-dozen countries began a major offensive against the de-facto capital of the "caliphate" in northern Iraq last Monday. It is not only the biggest coalition to have assembled in the fight against Islamic State (IS), it is also the least predictable.
The jihadists can be expected to commit any number of heinous acts in the hopes of holding onto their most important city, which is home of many of its leaders. The attackers, meanwhile, are part of an extremely fragile alliance: The US Air Force and Special Forces are contributing enormous firepower that can react quickly to realities on the ground. On the ground, meanwhile, the two strongest forces eye each other with suspicion: The Peshmerga fighters from the Kurdish Regional Government and the primarily Shiite militias of the so-called Popular Mobilization Forces. They forces were recently declared by decree to be Iraqi state troops, but are ultimately controlled by the Iranian Revolutionary Guards. The Shiite militias are feared, and have been accused of systematically expulsing, torturing and killing Sunnis. Furthermore, under the guise of fighting IS, they are suspected of conducting large-scale sectarian cleansing.
Officially, the Mosul operation is being led by the Iraqi army, which has been trained and equipped by the US since its collapse in 2014. But it can neither give orders to the other parties involved in the attack on Mosul nor is it militarily as strong. And then there are the 2,000 Turkish soldiers who have taken up position near Mosul, despite fierce objections from Baghdad -- and an unknown number of Kurdish fighters from the PKK in Turkey and Syria, troops who are actually at war with the Turkish army. Both contingents are kept apart by Iraqi-Kurdish generals.
It is a bizarre blend of low tech and high tech: American attack helicopters circle above the hazy landscape while Humvees belonging to the Iraqi army drive in a column with the Kia compacts belonging to the Kurdish fighters along with oil police patrol cars. On a pick-up flying the green-gold-black flag of the Shiites, a militia member jumps up and down to blaring music on the seat in front of his machine gun as the vehicle speeds down the road. Kurdish Peshmerga fighters and government soldiers need several interpreters to communicate with each other. It is a joint mission, they all insist, but they haven't even coordinated their radio communication.
Attack Could Get Nasty
Even so, Iraqi and American officials say that the first days of the attack, repeatedly pushed back for year now, were successful. Every day, they say, more villages are being liberated. Shakuli is one of them. On the edge of the village, near the military camp Khazir in the east, there is still the shredded, burnt-out wreckage of one of the monstrous vehicles that have proven to be one of IS's most horrifying tactical weapons: armored 20-ton trucks whose drivers can only peer out through a slit in the steel plating and whose beds holds several tons of TNT to blow up both the vehicle and the enemy.
"Nothing stops them, not machine guns, not even Russian anti-tank weapons," says a Kurdish officer on the edge of the village, "nothing except the Milan rockets provided by Germany."
But Shakuli is nothing more than a handful of houses on a slope that were abandoned by their inhabitants a year ago. A Kurdish artillery position on a hill a few hundred meters away bombarded the village for months while the jihadists took shelter in trenches and tunnels.
"Three or four of them are still there," says the Kurdish officer, adding that the village is now being filled with smoke from burning tires in order to drive them out. He doesn't want to risk his men on such a mission. The bodies of seven IS fighters lie, rapidly buried, where they died -- a dark-colored hand still protrudes from one of the piles of dirt.
Thus far, the expected mass exodus from Mosul has not come to pass because IS is holding the civilian population hostage: It has mined roads and is shooting people who attempt to flee. Two men, who were able to escape their IS-held village, cough as they list the names of villages from which inhabitants have been forced by IS at gunpoint towards Mosul: "Safina, Arfeila, Nusf Tell, Tuweiba, Tulu Nasr." And the list goes on, 14 villages in the immediate vicinity alone.
"Anyone who doesn't want to go is shot. Or they take their children and threaten to shoot them. They took four people from my family alone," one of the men says. They were marched closer to the city to be used as human shields and deter the jets from attacking.
Others say that hostages were taken. A group of soldiers from the 15 Division discusses whether the inhabitants might have gone of their own accord, but the surveillance officer shakes his head: "No. It is the same pattern everywhere. The civilians are being driven closer to Mosul."
Mosul itself is only about 40 kilometers (25 miles) from the southern front and only 15 km from the eastern front. But news from the city is thin, fragmentary and contradictory: Not long ago, it is said, unknown people began putting small notes into Korans in mosques with the words "Kill the Daeshis!", as IS followers are called in Arabic.
One source claims a general uprising has broken out. Another says everything is calm and that IS men are patrolling on motorcycles to avoid becoming easy targets for air strikes. A third reports that civilians are grouping together, armed with knives, and killing any IS fighters they encounter.
What's true? Nobody knows for sure. It's not even clear how many people are trapped in the city, formerly Iraq's second-largest metropolis with 2 million inhabitants. Is it 700,000 people? Or more than a million, as aid groups and the Iraqi government claim?
As well as the advance of the disparate allied forces has gone in the first few days, things could still turn bad. Thus far, IS has only used part of its arsenal: it has mined streets, bridges and houses, has posted snipers and has dialed in its artillery. But there's one type weapon it has yet to use: chemical weapons. In August 2015, IS fighters fired mustard-gas shells on the town of Marea, north of Aleppo. Peshmerga units in northern Iraq were later attacked with mustard gas and chlorine.
But where did Islamic State get these weapons? Chlorine, an industrial chemical, is easy to manufacture in large amounts. But mustard gas?
"There are several possible sources," says British chemical weapons expert Hamish de Bretton-Gordon. "It could come from Syrian stocks, or from old Iraqi stocks." There is evidence for both: The last reserves of the Iraqi chemical weapons program were secretly buried in the early 1990s. And the same circle of high-ranking secret service officers who supervised this operation is now connected to IS leadership. They are the ones most likely to know where the deadly shells were hidden.
Meanwhile, the Syrian chief negotiators who were supposed to have opened all storage spaces and laboratories after 2013, in addition to turning in all of the country's stockpiles didn't do so. According to an unreleased report by the Organization for the Prohibition of Chemical Weapons, the regime has primarily retained warheads filled with mustard gas. Experts speak of around 100 to 200 tons of mustard gas shells -- precisely the kind that have been launched by IS in the past.
Bretton-Gordon was once the commander for the British Joint Chemical, Biological, Radiation and Nuclear Regiment. He has recently travelled to Syria several times on the search for proof that the Assad regime used chlorine gas in attacks. There is, he believes, a third possibility for the origin of IS' mustard gas, one he believes to be the most likely: "We are now certain that IS is capable of producing mustard gas on its own. It has a slightly different composition than army stock, and is delivered in powder, not in liquid, form. Chemically, its production isn't that complicated." The site of production: "Probably Mosul."
Still, the homemade chemical weapons are not the most ominous threat, the expert says: "About 40 kilometers south of Mosul is the gigantic al-Mishraq sulfur plant. If IS blows that up, it could create a cloud of deadly sulfur-hydrogen compounds. It would be an Iraqi Bhopal," a reference to the 1984 disaster in Bhopal when thousands of people died after tons of poisonous materials were released from an Indian chemical plant.
On Saturday, reports emerged that Islamic State had indeed set fire to sulfur stocks at the plant, triggering a cloud of toxic smoke with Reuters reporting on Saturday afternoon that a hospital south of Mosul says nearly 1,000 people have been admitted with breathing problems as a result.
Anything could happen at any time: IS leaders and those who believe the propaganda about the coming apocalyptic war could set off doomsday by themselves. But the rumors from inside IS could also be true -- that discreet escape corridors to Syria may have been kept open in exchange for IS refraining from committing mass murder with chemical weapons. Observers from rebel groups in IS-held Syrian territory report having seen convoys of packed jeeps in the past several nights, and even during the day, arriving in Syria from Iraq.
Fighting might also break out in Mosul between those who would prefer to destroy everything than give it up -- and those who want to prevent a total destruction of the city. Informants are reporting that such fights are already taking place -- and the survival of hundreds of thousands of people could depend on the outcome.
Regardless how monstrously IS wants to deal with its military defeat in Mosul, its result could play into the jihadists' hands on the long term. Already, the allies on the frontlines are eyeing each other with suspicion. The only thing uniting them seems to be their common enemy and the goal of driving it from Mosul. Once that has happened, the allies of today could become the enemies of tomorrow. Several times, Iraqi Prime Minister Haider Al-Abadi has angrily told the Turkish army to pull out of Iraq.
Ankara's troops came in order to install the allied militia belonging to the former governor of Mosul, with its more than 3,000 fighters, as the city's rulers. Shiite militias, meanwhile, have announced their intention to attack the Turkish contingent -- though their orders come from Tehran, not from Baghdad. Mosul has become a playing field for various powers.
Officially, only the army and the federal police are supposed to enter the city itself, but the leader of the Shiite militias has repeatedly announced that he also wants to capture Mosul.
"We are afraid of everybody," said a man inside the city several months ago. "Afraid of the Daishis who occupy us. Afraid that the Shiite militias want to expel and kill us."
Tellingly, a blogger named Mosul Eye is hoping that Mosul will remain part of Iraq, but only under international oversight. Because, he says, you can't trust anybody in this country.
The article you are reading originally appeared in German in issue 43/2016 (October 22th, 2016) of DER SPIEGEL.
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