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Sanders on Climate Link to Terrorism

Sen. Bernie Sanders went too far with his debate claim that “climate change is directly related to the growth of terrorism.” One study concluded that man-made climate change likely worsened a drought in Syria and contributed to instability there. But the report stops short of drawing a direct causal link between climate change and the Syrian civil war, let alone between climate change and terrorism.

As the study’s lead author told us via email, the research “doesn’t deal with terrorism.”

SciCHECKinsertIn the Democratic debate on Nov. 14, CBS News political director John Dickerson asked Sanders if he stuck by his previous claim that the greatest threat to national security was climate change, given that Sanders has said he wants to “rid the planet of ISIS.”

“Absolutely,” Sanders said. “In fact, climate change is directly related to the growth of terrorism. And if we do not get our act together and listen to what the scientists say you’re gonna see countries all over the world– this is what the C.I.A. says, they’re gonna be struggling over limited amounts of water, limited amounts of land to grow their crops. And you’re gonna see all kinds of international conflict.”

On CBS’ “Face the Nation” the following day, Dickerson asked Sanders to expand on his statement that “climate change in fact is related to terrorism.”

Sanders, Nov. 15: Well, that’s not only my observation, John. That is what the CIA and the Department of Defense tells us. And the reason is pretty obvious. If we are going to see an increase in drought and flooding and extreme weather disturbances as a result of climate change, what that means is that peoples all over the world are going to be fighting over limited natural resources.

If there is not enough water, if there is not enough land to grow your crops, then you’re going to see migrations of people fighting over land that will sustain them. And that will lead to international conflicts.

I think, when we talk about all of the possible ravages of climate change, which, to my mind, is just a huge planetary crisis, increased international conflict is one of the issues that we have got to appreciate will happen.

Dickerson: But how does drought connect with attacks by ISIS in the middle of Paris?

Sanders: Well, what happens, say, in Syria, for example — and there’s some thought about this — is that, when you have drought, when people can’t grow their crops, they’re going to migrate into cities. And when people migrate into cities, and they don’t have jobs, there’s going to be a lot more instability, a lot more unemployment. And people will be subject to the types of propaganda that al Qaeda and ISIS are using right now. So, where you have discontent, where you have instability, that’s where problems arise. And, certainly, without a doubt, climate change will lead to that.

Some on the right scoffed at Sanders’ statements. On “Face the Nation” following Sanders’ appearance, the Wall Street Journal’s Peggy Noonan said Sanders’ comments made him “look slightly daffy, like someone who doesn’t understand what the real subject is.”

But Sanders’ summary of the position of the CIA and Department of Defense was accurate. They have been warning for years that extreme weather caused by climate change is likely to worsen instability around the world and cause security problems.

As we wrote in January, the Department of Defense referred to climate change as a ” ‘threat multiplier’ — because it has the potential to exacerbate many of the challenges we are dealing with today – from infectious disease to terrorism. We are already beginning to see some of these impacts.” Those threats are outlined in a report titled “2014 Climate Change Adaptation Roadmap.”

Department of Defense, Adaptation Roadmap, 2014: The impacts of climate change may cause instability in other countries by impairing access to food and water, damaging infrastructure, spreading disease, uprooting and displacing large numbers of people, compelling mass migration, interrupting commercial activity, or restricting electricity availability. These developments could undermine already-fragile governments that are unable to respond effectively or challenge currently‐stable governments, as well as increasing competition and tension between countries vying for limited resources. These gaps in governance can create an avenue for extremist ideologies and condition that foster terrorism.

As we also have written before, despite some claims to the contrary, there is some evidence that climate change is linked to more severe hurricanes, droughts and other weather disasters. Specifically, a report from the Intergovernmental Panel on Climate Change says that “there is medium confidence that some regions of the world have experienced more intense and longer droughts.”

This is the first link in the chain of logic that provides the basis of Sanders’ claim. In regard to climate change being “directly related” to Islamic State terrorism, the Sanders campaign points, in part, to a report called “Climate change in the Fertile Crescent and implications of the recent Syrian drought,” published in March in Proceedings of the National Academy of Sciences.

The authors analyzed the severity and frequency of droughts in the region and concluded that a severe drought in the Fertile Crescent region in 2007-2010 — just prior to the Syrian uprising — would not have been as severe or lasted as long absent a “century-long drying trend.” That trend, the authors contend, is the result of “human interference with the climate system.” In other words, the authors found that human-caused climate change “increased the probability” of the severe drought. The drought resulted in widespread crop failure and led to mass migration of farming families to urban centers, causing conflicts.

“We conclude that human influences on the climate system are implicated in the current Syrian conflict,” the authors wrote.

However, they cautioned, “civil unrest can never be said to have a simple or unique cause. The Syrian conflict, now civil war, is no exception.”

As for Sanders’ comment, lead author Colin Kelley told us via email, “My research doesn’t deal with terrorism.

“I would say climate change contributes to food and water insecurity, which in highly vulnerable nations (for many reasons) can lead to conflict,” Kelley said. “Beyond that I think it is fair to say that chaotic situations such as the civil war in Syria can allow extremism to flourish.”

So is climate change “directly related” to a growth in terrorism?

“In my opinion there is likely a causal relationship but that it isn’t necessarily a ‘direct’ one,” Kelley told us. “There are a lot of factors that contributed to the origination of the conflict and there are multiple steps between climate change and terrorism/extremism.”

Francesco Femia and Caitlin Werrell, codirectors of the Center for Climate and Security, told us via email that there is “certainly an indirect link” between climate change and terrorism.

Femia and Werrell, Nov. 16: The U.S. Department of Defense labels climate change a “threat multiplier.” Its impacts on food, water and energy security can create conditions that may increase the likelihood of state instability. And in ungoverned spaces, given the right political, economic, social and environmental conditions, terrorism can thrive, as we see in Syria. In other words, climate change could drive a less stable world, and non-state actors may exploit that. So it’s certainly an indirect link, which should not be oversimplified. This is not just our perspective. It comes from intelligence and defense communities here in the United States, and around the world, who are increasingly concerned about these dynamics.

But in a blog post and a Washington Post interview, they warned not to assign a direct causal link between the drought and the Syrian civil war, because the underlying dynamics of the Syrian crisis are too complex.

Femia and Werrell, Nov. 16: What is the biggest national security threat? Is climate change the biggest national security threat? We, and the current U.S. presidential candidates, get these questions quite a bit. They are not good questions. These questions confuse the nature of today’s security threats, and more specifically, obscure the complex way in which climate change affects the broader security landscape. Climate change is not an exogenous threat, hermetically sealed from other risks. It is, as the CNA Corporation first stated in 2007, a “threat multiplier.” The impacts of climate change interact with other factors to make existing security risks – whether it’s state fragility in the Middle East, or territorial disputes in the South China Sea – worse.

The Sanders campaign pointed to a 2003 Pentagon report that warned climate change “could contribute materially to an increasingly disorderly and potentially violent world.”

“The continuous violence, political disintegration, and massive migration we’re seeing in Syria and neighboring countries right now is precisely what the Pentagon warned us about over a decade ago,” a Sanders campaign spokesman related via email. “And it is exactly the kind of environment in which extremist groups like ISIS, al-Qaeda, and Hezbollah flourish. … Climate change is making terrorist threats … much worse.”

Indeed, a 2012 study by the National Research Council, commissioned by the CIA to evaluate the evidence on possible connections between climate change and U.S. national security concerns (summarized in the New York Times), concluded, “It is prudent to expect that over the course of a decade some climate events—including single events, conjunctions of events occurring simultaneously or in sequence in particular locations, and events affecting globally integrated systems that provide for human well-being—will produce consequences that exceed the capacity of the affected societies or global systems to manage and that have global security implications serious enough to compel international response.”

Similar sentiments have been expressed by the White House, the director of national intelligence and various military leaders.

In other words, Sanders has broad support for his claim that climate change is a factor in the terrorism equation, that it can contribute to and worsen tensions in some regions and lead to instability that poses security threats. But there is a complex web of causal factors behind the Syrian conflict and the Islamic State terrorism that has emerged from it. A study concluded that global warming “increased the probability” of a severe drought, a drought which contributed to displacement and mass migration, which contributed to instability, which may have contributed to violent conflict. But increasing the probability of a possible factor in a conflict isn’t the same as being a “directly related” cause for terrorism. The evidence so far does not support Sanders’ claim.

Editor’s Note: SciCheck is made possible by a grant from the Stanton Foundation.