By Erin Sikorsky, Caroline Baxter, Siena Cicarelli, John Conger, and Tom Ellison
Introduction
In the past year, the United States, its allies, and partners have faced unprecedented floods, wildfires, and heatwaves that caused thousands of deaths and billions of dollars worth of destruction and required the deployment of tens of thousands of troops. These hazards affect US foreign and security policy through multiple pathways, from the direct impacts on critical infrastructure and military resilience, to the amplifying effects on state fragility and conflict risk, food and water security, and geopolitical competition. The US Congress was prescient in warning of these risks in the FY2020 National Defense Authorization Act, signed into law by President Trump during his first term, in which climate security was defined as “the effects of climate change on the following: (A) The national security of the United States, including national security infrastructure; (B) Subnational, national, and regional political stability; (C) The security of allies and partners of the United States; (D) Ongoing or potential political violence, including unrest, rioting, guerrilla warfare, insurgency, terrorism, rebellion, revolution, civil war, and interstate war.”
Addressing the effects of climate change outlined above provides benefits across a range of foreign policy priorities for the United States, such as preventing instability, strengthening allies and partners, and improving operational resilience for the military. Additionally, preparing for and preventing climate-driven hazards protects US supply chains and increases US economic competitiveness.
In 2025, the new administration should redouble efforts to ensure a secure future for the United States by focusing on the following climate security actions:
- Prioritize domestic resilience to disasters
- Strengthen the US military’s competitive edge through improving its resilience to climate effects
- Invest in upstream prevention and resilience with US allies and partners
- Accelerate efforts to address global food and water insecurity
This briefer describes in more detail the pathways of climate security risk that are most concerning to the United States and outlines policy actions the incoming administration can take in the coming year to address these risks.