Democratic presidential contender Martin O’Malley sparked controversy this week by saying that the conditions for the rise of ISIL (ISIS, Daesh) were set by the impact on Syria of climate change, which drove farmers from their land into slums around cities and created extreme poverty. O’Malley’s assertion was immediately ridiculed on Fox News Channel and by Republican presidential hopeful Rick Santorum, who called the allegation a “disconnect from reality.” Who is right in this debate?

It should not come as a surprise that O’Malley is indeed correct, especially since he chose his words very carefully. He said, “One of the things that preceded the failure of the nation-state of Syria and the rise of ISIS, was the effects of climate change and the mega-drought that effected that region,” which “wiped out farmers, drove people to cities, [and] created a humanitarian crisis…. It created the symptoms, or rather the conditions of extreme poverty that has led now to the rise of ISIL and this extreme violence.” O’Malley did not attribute the radical extremism in northeast Syria only to climate change and drought, underlining that it was only one of the causes of the weakening of the Syrian state and the immiseration of the population, which made them so desperate that they even turned to Abu Bakr al-Baghdadi and his hateful beheaders for salvation. It was, however, one cause among others, he said.

Professor Hannu Juusola of Helsinki has shown in a scholarly article that in the northeast of the country—the seat of power of ISIL in Syria—between 2006 and 2010, 70 percent of farmers’ livestock died because of severe drought. Wheat production declined 18 percent in a single year, and 3 million people in the northeast were already food insecure five years ago. Syria’s underground water aquifers are few and becoming depleted or polluted. Syria is part of a vast Middle Eastern arid zone and has, of course, been subject to cyclical drought throughout history. But drought is exacerbated by higher temperatures, and we know that the world is about a degree Fahrenheit warmer now than in 1850 because since then we’ve been spewing billions of tons of powerful greenhouse gasses such as carbon dioxide and methane into the atmosphere every year. Hence, this drought is worse than previous ones. (Other scientists have confirmed Juusola’s findings.)

All this would not matter as much if Syria was a largely urban society, but 45 percent of its residents before the turmoil that began in 2011—some 9 million people—were rural. Largely urban societies such the United Arab Emirates (a wealthy oil state that has desalinization plants for making potable water from sea water) are not as badly affected by severe drought, since most residents just need drinking water. But 90 percent of Syrian water is used for irrigation, and a shortfall is a social disaster. It is probably also the case that as it came under pressure to join the march to neoliberalism in the 1990s and after, the Syrian regime privatized many economic activities, and its officials may have been more interested in lining their pockets than in using state resources to address the water crisis.

As O’Malley correctly observed, failed farmers lacking water abandon their farms and go to the city in search of day labor as construction workers. Central Sunni cities such as Hama and Homs were circled by shanty towns thrown up by these economic refugees from the countryside, and those shanty towns were a major site of social protest in 2011. Likewise, some initial protests in the southern city of Deraa in 2011 were demonstrations by farmers and food distributors over the lack of water in the countryside. When the Syrian army shot down the protesters, they picked up weapons and gradually became radicalized in their fight against a secular, socialist, and Shiite-dominated Syrian state. For ideological clarity, it was advantageous for the new rebels to be everything the state was not, i.e. hard-line Salafi Sunni fundamentalists. Hence the appeal of ISIL, and of the Al Qaeda–linked Jabhat al-Nusra. The turn to ISIL was not inevitable, and there were other possible responses to the drought (the Kurds of the northeast, who also experienced water shortages, have increasingly broken with the regime but are instead attracted by a kind of feminist, post-Marxist, anarchistic, socialism). But that it exacerbated social tensions between the regime and rural Sunni Arab populations of the heartland and the arid east seems uncontroversial.

O’Malley’s statement provoked howls of outrage on the American right because it challenged two deeply held fantasies. The first is that the earth is not rapidly warming as a result of human burning of coal, gas, and oil. The second is that Muslims are intrinsically given to violent fundamentalism. The scientific evidence for global warming is incontrovertible. As for Muslims, they have adopted all sorts of politics in the modern era. The Uzbeks went Communist for a long time, the vast majority of Tunisians rather like democracy, and the majority of Egyptians have been allergic to religious fundamentalism, while even most religious conservatives in Egypt have rejected violence. The idea, moreover, that heterodox groups such as Lebanese and Israeli Druze, Turkish Alevis, or Syrian Alawites would have any truck with radical Sunnism is laughable. That a violent fringe exists in the Muslim world is undeniable, but it isn’t an essence of Muslims any more than violent separatism, which produces most terrorism in Europe, is intrinsic to Christians.

The bad news is that O’Malley’s observation about ISIL and Syria is only the beginning. The Middle East is in the crosshairs of climate change more than most of the world. Sea-level rise will flood the low-lying Egyptian Delta, where the bulk of the population is and where most of the country’s indigenously produced food is grown. It will also push Mediterranean salt water up the Nile, making the soil barren around it. Even in the next few decades, there could be devastating storm surges affecting cities like Alexandria and Damietta.

Yemen as a country may simply have to move house. The aquifer beneath the capital, Sanaa, is being rapidly drawn down, and the capital may have no water in as little as five years. Severe drought and water shortages in the rest of the country have damaged agriculture and have contributed to livestock die-offs in the outskirts of cities such as Taiz. Some of the violence and radicalization seen in Yemen, which has led to the country’s partial take-over by Houthi rebels and an intensive Saudi aerial bombardment in the past few months, is rooted in the social dislocations to which climate change has contributed.

Moreover, an important part of the Arab-Israeli conflict has been driven by struggles over water, which will be exacerbated as that precious fluid dries up.

Climate change in the Middle East is a security issue for the countries of that region and for the United States. GOP blindness to this problem and insistence on continuing to put 5 billion metric tons of carbon dioxide into the atmosphere every year is contributing to a set of disasters for the United States and the world. O’Malley should be praised for saying this forthrightly, though it is a sad commentary on American politics that his statement of fact should be a matter for congratulation, or that it should have been met with derision from the ignorant.