Climate & National SecurityHow Climate Change Will Impact National Security

By Christina Pazzanese

Published 28 November 2021

The recent U.S. National Intelligence Estimate (NIE) lays out the likely security implications over the next two decades of the mounting climate crisis. Calder Walton, the research director at Harvard’s Belfer Center, says: “Let’s start with the basics: that climate change does pose a threat to U.S. national security. The National Intelligence Estimate is a joint assessment produced by the entire U.S. intelligence community, 18 agencies. That’s significant. There are no naysayers; there’s no doubt. So that’s a breakthrough. In this extraordinarily polarized and politicized environment, that is a big milestone itself.”

Rising temperatures and intensifying weather due to climate change, along with the unlikelihood of meeting the 2030 emissions goals of the Paris Agreement, will exacerbate geopolitical tensions, social instability, and the need for humanitarian aid, according to a joint report by the U.S intelligence community last month. The National Intelligence Estimate lays out the likely security implications over the next two decades of the mounting climate crisis. Calder Walton is assistant director for research at the Belfer Center’s Intelligence Project, which organized Harvard Kennedy School’s first conference on climate change and national security last spring. He spoke with the Harvard Gazette’s Christina Pazzanese about the report and the important role the intelligence community should play in addressing the crisis.

Christina Pazzanese: We hear about the threats posed by climate change from an environmental standpoint, but rarely about the risks and threats it poses to national security. How does the U.S. intelligence community view climate change, and is this a new domain?
Calder Walton
:The purpose of the U.S. intelligence community, established after the Second World War in the wake of Pearl Harbor, was to provide policymakers with decision advantage and forewarning of threats to national security. If the primary purpose is to give decision advantages about national security threats, obviously, by definition, the U.S. intelligence community has to have a role giving key decision-makers their assessments about the greatest existential threat in human civilization: climate change. What is going to be the impact of changing climate on national security, economic society, civil society? And this isn’t just national security; this is international, globalized security. If we look at it like that, clearly, the U.S. intelligence community has to have a role. And they’re very, very late to the game.

Pazzanese: How are other intelligence services responding to climate change? Is any country leading the way?
:  I don’t think anyone is a shining star in terms of taking this seriously. I have yet to find an example of a country that has an intelligence bureaucracy set up to really deal with this and to provide assessments about the national security implications of climate change to policy leaders in a sufficient way.