It’s the dog days of summer for U.S. presidential candidates, when Donald Trump is dominating the airwaves and candidates who seem to be losing their purchase at the polls are doing whatever they can to capture some attention—whether that’s taking a chainsaw to the tax code, like Rand Paul, or claiming there’s a connection between ISIS and climate change, like Martin O’Malley.

“One of the things that preceded the failure of the nation-state of Syria and the rise of ISIS was the effect of climate change and the mega-drought that affected that region, wiped out farmers, drove people to cities, created a humanitarian crisis that created the symptoms—or rather, the conditions—of extreme poverty that has led now to the rise of ISIL and this extreme violence,” the Democratic candidate told Bloomberg on Monday.

Actually, hold that thought on O’Malley. His comment was noted by the Republican opposition-research organization America Rising and promptly mocked by conservative media outlets. The Republican National Committee issued a statement ripping O’Malley, which he was probably happy to get.

But O’Malley’s comment isn’t as weird as it might initially seem. There’s an established body of work that draws a connection between drought, resource scarcity, and conflict in general. In a 2013 article for The Atlantic, William Polk, a historian and former adviser to President Kennedy, noted a possible relationship between Syria’s civil war and devastating 2006-2011 drought. “As they flocked into the cities and towns seeking work and food, the ‘economic’ or ‘climate’ refugees immediately found that they had to compete not only with one another for scarce food, water, and jobs, but also with the existing foreign refugee population,” he wrote. “Formerly prosperous farmers were lucky to get jobs as hawkers or street sweepers. And in the desperation of the times, hostilities erupted among groups that were competing just to survive.”