On April 21, Saudi Arabia officially ended a military intervention in Yemen dubbed "Operation Decisive Storm." Reacting to a rapid expansion of rebel Houthi militias and their allies, who had effectively toppled the government of Yemeni President Abd Rabbu Mansour Hadi, the government in Riyadh had less than four weeks earlier launched a blistering Western-aided aerial assault on opposition lines. On that Tuesday in April, the Saudi government released a statement declaring that the operation had "achieved its goals… removing the threat to Saudi Arabia and neighboring countries."

But the fighting didn't stop, and the bombing didn't either. Soon after, Saudi officials acknowledged that the intervention had in fact not ended and said it would continue to target the Houthis. According to the UN's human rights agency, more than 2,700 civilians have been killed since Yemen's conflict escalated in late March, struck down by airstrikes, indiscriminate shelling, and gunfire. At least a further 5,300 have been injured.

As Yemen enters 2016, it faces an unprecedented humanitarian crisis and a war that has no apparent resolution in sight. UN-brokered peace talks ended earlier in December without result, their greatest achievement simply having been that they occurred at all.

"There has never been a moment in the history of Yemen this bad," said Farea al-Muslimi, a Yemeni activist and visiting scholar at the Carnegie Middle East Center. "Both sides are losing command and control. If at one point one side decides they do want peace, I don't think they will be able to control it — neither the Houthis nor the Saudis."

Just four years ago, Yemenis pushed out longtime strongman Ali Abdullah Saleh and regional powerbrokers oversaw a transition to a new government under Hadi. Amid the Arab Spring, there was cautious optimism that the country could establish a more inclusive government and help bring millions of Yemenis out of poverty. Instead, restive factions clamored, including the long-marginalized Houthis.

Their militias, made up predominantly of Zaydi Shias and aided by forces loyal to Saleh — who had just a decade earlier fought a series of wars with the Houthis — eventually took up arms and, facing little opposition, seized Yemen's capital of Sanaa in late 2014. After fits and starts, the Houthis and Saleh's army units descended south, capturing the Western coast of the country.

Hadi fled to Saudi Arabia. On March 26, the Saudis, leading a coalition of Sunni Arab states, began bombing Yemen, ostensibly on Hadi's behalf.

'The Yemeni people didn't choose war, but they are suffering from it.'

Aided by American logistical and intelligence support, including what Washington calls "targeting assistance," the Saudi-led coalition and local forces were able to push the Houthis from some areas, including the southern port city of Aden. But today the Houthis still control Sanaa and large swaths of the north and west of Yemen.

International human rights organizations have documented the deaths of hundreds of civilians resulting from airstrikes — attacks that may constitute war crimes. Last week, Zeid Ra'ad al Hussien, the UN's high commissioner for human rights, told the Security Council that his office had documented human rights violations by all sides, but added that a "disproportionate" number of attacks on civilians "appeared to be the result of airstrikes carried out by coalition forces."

In October, Amnesty International called for Western countries to cease arm shipments to the Saudis. A month later, the US approved a $1.29 billion weapons deal that would help replenish supplies spent in Yemen, including bombs that have been explicitly tied to civilian deaths.

Human Rights Watch argues that the US should be considered a party to the conflict due to its involvement with the Saudis, which includes a coordination cell in Saudi Arabia staffed with American personnel and regular American tanker flights over Saudi airspace that have refueled coalition aircraft more than 2,000 times.

HRW has called on US officials to investigate civilian casualties, but there is no evidence that Washington is doing so. Instead, American officials refer queries to the Saudis, who provide little information on attacks. When they do, Saudi statements are often contradictory, or they simply deny that the coalition dropped bombs despite being the only airpower in most of the country. (The US continues to operate a drone program targeting al Qaeda, which the UN estimates from July 1, 2014 to June 30 of this year may have killed more civilians in Yemen than the terror group did itself.)

Hadi has been able to make intermittent trips to Aden, but security there is tenuous at best. On December 6, Aden's governor was assassinated in a car bombing, an attack claimed by an affiliate of the Islamic State (IS). Like al Qaeda's franchise in Yemen, fighters claiming allegiance to the Syria-based IS have seized on the power vacuum.

Elsewhere, much of Yemen has been laid to waste, perhaps most critically in the northern province of Sadaa, a Houthi stronghold that has borne the brunt of countless coalition strikes. Trond Jensen, head of the UN's Office for the Coordination of Humanitarian Affairs in the country, returned recently from Sadaa city, where he said "all the public buildings have literally been destroyed."

"We met with IDPs there, and one of the people I was introduced to was an 11-year-old girl," he said in an interview from Sanaa. "This 11-year-old girl was the head of her family after her father was killed in an airstrike. Her older sister was blinded, and the mother had fled, leaving her in charge of her 5 siblings."

In Sadaa, the girl was lucky to be alive. Across all of Yemen, the UN says over 600 children have been killed this year, along with 900 that suffered grievous injuries.

"It makes you realize how vulnerable people are being made, and particularly what is done to children, who are ill-equipped to live through this," said Jensen. "A generation of children are traumatized and in need of psychosocial counseling."

Though figures are hard to come by, the number of female-headed households in Yemen has risen considerably during the war. But despite their vital role in holding together what remains in Yemen, women are vastly underrepresented in political discussions.

Jensen, who has worked in Yemen for three years, says the humanitarian situation in the country is now teetering on catastrophe. Already the poorest country in the Arab world, some 7.6 million people in Yemen are currently considered food insecure, on the verge of starvation. The war has undone progress made to improve access to food, and now more than 300,000 children under five are suffering from severe malnutrition.

"That means they are in real danger of dying," said Jensen.

Since March, Riyadh's coalition has maintained a blockade of the country, causing supplies of basic goods**,** food, and fuel to dwindle — and their prices to skyrocket — within a few months. As recently as September, the UN estimated that commercial fuel imports stood at a meager 1 percent of what Yemen needs. A UN inspection mechanism meant to vet commercial supplies entering from sea is still not up and running. Though Jensen said more legal imports had made their way into the country towards the end of this year, the dismantling of Yemen's economy has left many of its citizens with no money to buy food if it trickles in. "What we have seen is people are adopting unsustainable coping mechanisms — which is either that they start eating less food or they borrow money to acquire food," he said. "People's savings are running out."

Even in areas where the UN and its local humanitarian partners have been able to transport food and emergency supplies, armed groups on the ground, often the Houthis, have prevented it from being distributed. In Taiz, where fighting has only worsened in recent months, more than 200,000 people live under a virtual state of siege amid coalition strikes and indiscriminate shelling from Houthis and allied forces. Jensen said about 3,000 tons of food had been delivered to the city's vicinity, along with 20 tons of medical supplies, but most of it had not yet reached those in need. According to UN estimates, half the city's existing water and sewage infrastructure no longer functions.

Amid the destruction of public services, Jensen said that many civil servants have thanklessly continued carrying out their jobs without payment.

Radhya Almutawakel, co-director of the Sanaa-based Mwatana Organization for Human Rights, has worked with colleagues in Taiz to document violations committed in the city. She said places like Taiz are at a critical juncture, when long-suffering residents may become irreversibly polarized.

"Right now, people say our house is here and the shell just came from the west or the north, and we know this place is controlled by this group or that group," said Almutawakel. "Most people have anger for all groups, but if the conflict is just to continue, people will be more and more divided."

Speaking from the capital, where coalition jets buzz overhead daily, Almutawakel lamented how deeply the fighting has set back the political and social gains of recent years. Civil society has been particularly affected, as an increasingly paranoid Houthi leadership jails activists and journalists and shutters media outlets.

"At a certain time, people started to talk about the constitution. They used the courts, they went to the police station," said Almutawakel. "The situation was never good, but we still had these tools and we used them to a certain level, but now that's completely damaged, and we don't have these things."

"The Yemeni people didn't choose war, but they are suffering from it," she added. "If the war continues, then war will be the only thing that people can do. Most are still victims, civilians, but with time they will not be civilians anymore."

The worst outcome, she concluded, was the increased fragmentation andlocalizing of fighting forces. Like Muslimi, Almutawakel said the divisions after nine months of war are in some ways even worse than those during a 1994 civil war that resulted in the uniting of the Yemen's north and south under Saleh's rule.

Many armed groups that have fought the Houthis and Saleh's forces in the south have made it clear that they will not continue north. Riyadh has shipped in at least hundreds of soldiers from Sudan, whose president, Omar al-Bashir, remains indicted by the International Criminal Court for genocide, while mercenaries from Latin America have reportedly entered Yemen under the guidance of the United Arab Emirates, another coalition member.

"The Saudi Yemen coalition cannot be described as anything other than contradictory and chaotic," said Charles Schmitz, a professor at Towson University and an expert on Yemen. In the south, many resistance forces have demanded to be officially incorporated into Hadi's army, but thus far "have largely fought on their own with little support," he said. In the north, some of the commanders ostensibly supporting Hadi against the Houthis have ties to units that southern secessionists — now also targeting the Houthis — harbor resentment against due to abuses during the civil war. Alliances are schizophrenic, cynical, and often merely nominal.

"As an illustration of the chaos, al Qaeda managed to take control of the main port city of eastern Yemen, Mukalla, and advance on Hadi's hometown in Abyan Governorate close to Aden," said Schmitz. "The Hadi government appears incapable of reining in al Qaeda or providing even minimal security in the areas it nominally controls."

Meanwhile, Schmitz said, Saleh remains intent on preserving a role for his family and political dynasty in the country. The Houthis, he added, "want to normalize their dominant position in Yemeni politics" and "cash in on their military gains for a partnership stake in the future Yemeni state."

Until now, the Hadi government and its Saudi-coalition backers have insisted the Houthis comply with a UN Security Council resolution that ordered their retreat from all seized territory, including Sanaa, and for them to lay down arms. That, said Schmitz, is a non-starter for the Houthis and Saleh.

In the enduring conflict, fissures have begun to emerge along sectarian lines — a worrying sign, said Muslimi, who in a recent piece for Carnegie pointed to groups on both sides that have begun branding militias and brigades after sectarian or regional names.

Saudi Arabia accuses its regional rival Iran of backing the Houthis, though the level of that support remains unclear. Among many analysts, the conflict is often seen through a simplistic lens similar to that applied to the civil war in Syria, where Tehran has helped prop up the regime of President Bashar al-Assad while the Saudis and other Gulf nations have lent backing to Sunni rebel forces. Though the strife in each country is different in countless ways, views such as these, and regional powers acting on the fears they inspire, could lead to a self-fulfilling prophecy.

"If you are talking about any social coherence, it has been distorted or damaged," said Muslimi. "We will wake up and we are already in Syria."