A guard sits on the rubble of the house of Brigadier Fouad al-Emad, an army commander loyal to the Houthis, after Saudi-led coalition air strikes destroyed it in Sanaa, Yemen, June 15, 2015. (Khaled Abdullah/Reuters)

Peace talks to resolve Yemen’s war between a Saudi-led coalition and Houthi rebels ended in failure on June 19 in Geneva. This was unsurprising. An initial attempt to hold peace talks in late May collapsed before talks even started. On separate occasions in May and April, combatants refused to observe cease-fires to allow for the delivery of humanitarian relief. Even after Yemeni delegates reached Geneva in mid-June, they refused to meet face-to-face, forcing U.N. officials to shuttle between rooms.

The war in Yemen is bound to prove difficult to end because of the sharpness and history of divisions in a country with only a short experience of national “unity.” Protracted conflict is likely to worsen the expanding humanitarian crisis – 21 million Yemenis need humanitarian assistance – and create a dangerous political vacuum in which militant supporters of al-Qaeda and the Islamic State could flourish.

Many analysts depict the current fighting as a proxy war between Saudi Arabia and Iran. Others describe it as a sectarian conflict between Muslims who identify with opposite sides of the Sunni-Shiite split, which of course also characterizes Saudi-Iranian tensions. There are elements of truth to both perspectives, yet they over-simplify a complex problem. The real reason that war may prove impossible to end while maintaining territorial integrity of the country is: Yemen lacks national cohesion.

Yemen has lacked cohesion from the start of its historic unification in 1990. Within two years, a string of political assassinations poisoned the atmosphere leading to civil war in 1994. Thereafter, unity was only maintained by military force as then-President Ali Abdullah Saleh consolidated gains on the battlefield, while strangling the population’s political and civil rights. Yemen has a long history of warfare and assassination, and it has never enjoyed long periods of stable government under one national ruling authority. Instead, its past is characterized by multiple authorities and regional fragmentation.

The reality of Yemen’s lack of cohesion is too often ignored by powerful outside actors, such as Saudi Arabia and the United States, who fear greater instability and insecurity if the country breaks apart. Before the current war, it was largely outsiders who pretended Yemeni unity was real, just as it was foreign governments and lending institutions that pumped funds into a country chronically on the verge of bankruptcy.

During the past two decades, those in local leadership were supremely aware of how this game is played. They became adept at drawing outside aid from as many foreign sources as possible, while posing as champions of Yemeni national interests without truly representing the people. Since 2011 Saudi Arabia, in collaboration with other the Gulf Cooperation Council (GCC) states, has been heavily invested in forming a new Yemeni government.

A similar dynamic existed at the recent Geneva talks. None of the delegates represented large constituencies at home, while many of the main factions involved in fighting were not even invited. Houthi delegates in Geneva might represent the largest constituency. Yet, the size of their support is often exaggerated by journalists who admire the former rebel group’s underdog status in the early 2000s and embrace the group’s rhetoric of combating corruption and poverty. Given Yemen’s demographics – the majority of the population lives outside of traditionally Zaydi areas – it seems unlikely that the Houthis have the support of even one-quarter of the population.

Houthi control would be at odds with the demands of Yemeni protesters who rallied for progressive change, good government, social justice and regional self-rule during the Arab Spring. The majority of citizens oppose Houthi leaders because they represent anti-revolutionary values from pre-1962, when northern Yemen was ruled by a Zaydi monarchy historically based in Sada, which is the Houthi homeland. The Houthis recently appeared to gain power after forging a temporary alliance with former president Saleh, who was forced to resign following the protests in 2011. Saleh fought six wars against Houthi rebel forces between 2004 and 2009, but in 2014 he leveraged them to exact revenge against mutual rivals among the Yemeni branch of the Muslim Brotherhood. Recently, Houthi leaders have positioned themselves as “leading defenders of the nation,” but their alliance with Saleh betrays not only the popular 2011 revolution, but also the revolution that ended Zaydi rule in 1962. They simply have no chance of uniting the country from north to south and east to west.

In January, when President Abed Rabbo Mansour Hadi unveiled a new constitution derived from outcomes of the national dialogue that concluded in 2014, Houthi fighters moved forcefully with Saleh’s troops against the president by kidnapping his chief adviser and surrounding his home with tanks. Saleh and the Houthis primarily opposed the new constitution because it included the national dialogue’s most significant recommendation: a new federal structure of the Yemeni republic. Though the recommendation came out of the 2013-2014 dialogue, it is part of the broader GCC diplomatic effort started in 2011 to create a stable political transition post-Saleh.

The opposition of Saleh and the Houthis to the federal constitution is the most important reason for the war. Houthi officials voiced their disagreement with the boundaries of six new federal regions, saying they wanted to include a Red Sea port in the designated region for Yemen’s capital Sanaa. Hadi and his advisers tried to placate their concerns, acknowledging that federal borders could be redrawn at a later time. The federal map was created after hard compromises among many regional representatives, so Houthis were not the only ones expected to accept less than they desired.

The Houthis and Saleh were not only interested in having a port on the Red Sea. They objected more fundamentally to the federal plan because it would have reduced their overall power and influence. They sought control of the entire country, as indicated by their later military actions. Across history, the traditional Zaydi region of Yemen between Sada and Sanaa has lacked valuable resources, so its leadership has long used conquest to pillage sources of wealth elsewhere. Any federal decentralization of power represents a direct challenge to the Zaydi group’s interests. That explains why Saleh – who hails from the Zaydi region – opposed real decentralization during his nearly four-decade tenure.

As president, Saleh regularly accused federalism advocates of being traitors. For example, before the 1994 civil war, when his southern socialist political partners in unity advocated federal reforms, Saleh accused them of a foreign conspiracy with Saudi Arabia. He launched the 1994 war as an act of aggression to conquer southern provinces. Once it ended, much of the southern population continued to feel it lived under northern military occupation. This sentiment is in part what the 2011 GCC plan and national dialogue were intended to address.

The GCC-led effort to constitute a new federal government in Yemen was the last, best chance to create a stable, semi-united country. Federalism was never a perfect solution to Yemen’s problems. In many ways, it was too late in 2012-2015 to think of reform along federal lines. Across the 2000s, Yemen became a failed state long before the Arab Spring because its institutions had disintegrated under the weight of internal rebellions. Ideally, the federal option should have been adopted in the early 1990s when many Yemenis advocated it as the best way to overcome the problems of national unification. Federalism may not have enjoyed high odds of success in 2012-2015, but there simply was no better option to hold the country together.

Today, it is difficult to imagine Yemen being restored as a single nation-state. There is no center of gravity, and among multiple local authorities, no one firmly controls more than a quarter of the country. It is past time for world leaders to deal realistically with Yemen’s problems.

Denial of its regional divisions and ignoring the need to decentralize powers of political and economic decision making outside the traditional Zaydi region around Sanaa, will perpetuate armed conflict for years to come. Although today’s priorities must be to stop the war and send emergency humanitarian assistance to the population, Saleh, Houthi and other elites in Sanaa should never again be allowed to monopolize political and economic control of the country.

Stephen W. Day is professor of international affairs at Rollins College and author of “Regionalism and Rebellion in Yemen: A Troubled National Union” (Cambridge 2012). Follow his regular commentary on developments in Yemen on Twitter @DaySWTweet.