Sen. Bernie Sanders speaks at the Fair Immigration Reform Movement presidential candidate forum on Nov. 9 in Las Vegas.AP Photo/John Locher

This article is from the archive of our partner National Journal

What’s a greater threat, climate change or ISIS?

Democrats often draw GOP and conservative attacks when they talk about the national security dimensions of global warming.

The latest flare-up: Early in Saturday’s Democratic debate, one refocused on terrorism after the Paris attacks the day before, CBS moderator John Dickerson gave Bernie Sanders a chance to back off his recent claim that climate change is the greatest security threat facing the country.

Sanders didn’t budge, saying he “absolutely” still believed it.

“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 going to see countries all over the world—this is what the CIA says—they’re going to be struggling over limited amounts of water, limited amounts of land to grow their crops. And you’re going to see all kinds of international conflict,” he added.

The question, Sanders’s reply, and the conservative pushback against him—tallied by the liberal group Media Matters—represents the latest public airing of the idea that somehow these threats can be ranked in comparison with each other.

For Republicans and their conservative allies, discussion of the nexus between climate change and national security often provides a political opening to call Democrats weak on terrorism.

Just a day after the massacre in Paris, the right-wing website Breitbart posted a compendium of times that President Obama and other officials have emphasized the security threat of climate change.

That’s hardly the first time that Democrats from Obama on down have gotten pushback from the Right. In September of last year, before Hillary Clinton or Rand Paul had officially entered the White House race, Paul jumped all over her claim that “cli­mate change is the most con­sequen­tial, ur­gent, sweep­ing col­lec­tion of chal­lenges we face.”

“I don’t think we really want a com­mand­er in chief who’s bat­tling cli­mate change in­stead of ter­ror­ism,” Paul said on Fox News. (Clinton, perhaps hoping to avoid that minefield, said in her campaign-launch speech nine months later that climate change is “one of the defining threats of our time.”)

The Clinton-Paul dust-up was reminiscent of an early 2014 episode, when Republicans John McCain and Newt Gingrich attacked John Kerry for calling climate change “per­haps the world’s most fear­some weapon of mass de­struc­tion.” Kerry said it “ranks right up there with terror, epidemics, poverty, and nuclear proliferation.”

Politically, it may be fertile ground for conservatives to use climate change as a vehicle for arguing that Democrats are screwing up on terrorism. After all, polling shows that defending against terrorism is a far, far higher priority than global warming.

But politics aside, questions about ranking security threats—especially such disparate types of threats—may not make much sense.

Daniel Chiu, a former high-level Defense Department official who worked on planning for climate-related risks, says the idea of creating a simple ranking of threats is “understandable, but it is just wrong.” Chiu equates the question to asking what’s more important, food or water.

“You can’t just rack and stack challenges, risks, threats,” said Chiu, the former deputy assistant secretary of Defense for strategy and force development. Risks are a calculation of probability and consequence, he notes, and climate change and terrorism don’t lend themselves to apples-to-apples comparisons.

“The consequences [of climate change], especially if left unchecked, can, according to the scientific community, [be] extremely high but very long-term,” said Chiu, who left the Defense Department late last year and now has a senior role at the Atlantic Council. “Then you have things like terrorism—near-term, in your face, significant, absolutely—but we are not talking about global. So how do you trade off—how do you say which one is more, which one is less? These are different kinds of threats; they are not one-is-more, one-is-less kinds of threats.

“When it comes to people saying, how do you rank-order these and tell me which are your priorities; my answer is, we actually have to deal with both of these things,” Chiu said.

Defense and intelligence officials, including Chiu, have for years been studying how climate change will affect national security, though as Vox notes, Sanders’s claim that climate change is “directly related” to the growth of terrorism goes beyond what analysts typically argue.

Their view is generally that climate change will exacerbate problems—such as drought, flooding, and food price changes—that create instability and can fuel migration and conflict, especially in weak or chaotic states.

The Defense Department’s latest Quadrennial Defense Review in 2014 concluded: “These effects are threat multipliers that will aggravate stressors abroad such as poverty, environmental degradation, political instability, and social tensions—conditions that can enable terrorist activity and other forms of violence.”

A widely circulated study published this year in the Proceedings of the National Academy of Sciences is especially relevant to today’s conflict with ISIS in Syria and Iraq.

It found that human-induced climate change likely contributed to the extreme drought in Syria in 2007-2010. Those conditions worsened problems in the country as crops failed and there was a mass migration to urban areas, adding to the instability that led to an uprising in 2011.

But the notion that the risks of climate change and other forms of security threats can be neatly placed into a hierarchy is really dicey and problematic.

For one thing, a number of the main strategies for battling terrorism and battling climate change are different, and reside in different parts of the government. Increasing military attacks against ISIS doesn't help fight global warming.

Bolstering renewable energy and putting a price on carbon isn’t a near-term or even medium-term strategy against terrorism, even if stemming runaway climate change is a check against instability in the long term.

And strategies for tackling one problem don’t typically some at the expense of the other either. Imagine for a moment that President Obama walked away from his effort to cut carbon emissions from coal-fired power plants. Those personnel working on the rule are unlikely to transition to, say, gathering intelligence on ISIS movements in Syria and Iraq.

But that’s not to say that federal agencies with a direct security role don’t have to make choices about where to use their resources, and Republicans have taken aim at efforts by defense and intelligence agencies to weigh the risks of global warming, arguing it detracts from other work.

Sen. John Barrasso, at a Foreign Relations Committee hearing last year on the security implications of climate change, said Obama administration spending on international climate programs and Defense Department analyses detracts from tackling security risks.

“I believe taxpayer money would be better spent improving the security of U.S. embassies, protecting our service members who are serving the nation in often dangerous locations across the globe, and fighting terrorism and bad actors that wish to do us harm,” Barrasso said.

Chiu and other analysts, however, say that studying climate change and how it may affect military infrastructure and future actions is vital.

Michael Werz, who has studied the nexus between climate change and security risks, said confronting existing threats such as ISIS and long-term strategic planning that incorporates climate change are both necessary.

“This is not a trade-off. We have to do both at the same time,” said Werz, a senior fellow at the Center for American Progress.

He said it’s vital to end “silos” between diplomacy, defense, and development planning. “What we need to do is move to a post-Cold War mindset and rethink all the categories and criteria that we have applied to security threats,” Werz said.

This article is from the archive of our partner National Journal.

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