Climate Change and Security

Climate change affects far more than the environment—it fundamentally shapes national security challenges facing the United States. As resource scarcity, food insecurity, and unstable borders intensify, they create conditions for increased conflict, political instability, and mass displacement. Understanding how climate impacts security policy helps explain why military planning, intelligence assessments, and defense strategies have incorporated climate considerations. Yet approaches to addressing this challenge have evolved significantly, reflecting changing priorities across administrations.

How Climate Change Threatens Security

Climate-related stressors create direct security risks. Rising temperatures correlate with increased violence—a one-degree Celsius increase can raise interpersonal violence by roughly 2% and intergroup conflict by 2.5% to 5%, largely driven by resource shortages. As water becomes scarce and crops fail, food insecurity spreads, triggering mass migration and climate refugees. These pressures worsen existing tensions within and between nations, while simultaneously exacerbating issues like terrorism and extremism. Learn why climate change is now treated as a national security threat to understand how these connections shape policy thinking.

Government Response and Strategic Priorities

For over a decade, U.S. intelligence agencies and the Pentagon acknowledged climate change as a serious national security concern. Explore the Pentagon’s climate strategy, its past priorities, and new direction to see how military planning has adapted to these challenges. However, current administration policy reflects a different approach—the 2025 National Security Strategy explicitly rejects what it characterizes as “climate change” and “Net Zero” ideologies, marking a significant shift in how climate considerations are weighted against other national priorities.