1. United States
2. Colo.
3. Letter

It is long past time to confront a truth that has been treated as politically inconvenient: the United States military is one of the single largest drivers of planetary destruction, and you have allowed it to operate with virtually no environmental oversight, no meaningful emissions reporting, and no accountability. The new documentary Earth’s Greatest Enemy lays out what researchers, veterans, and frontline communities have been saying for decades — and what Congress has consistently refused to act on: the U.S. military is the world’s biggest institutional polluter, and its environmental footprint poses a direct threat to human life, national security, and global stability. The numbers are staggering. The Department of Defense reports roughly 55 million metric tons of CO₂-equivalent emissions per year — a figure that alone would make it one of the largest emitting institutions on Earth. But that number is only a fraction of the truth. Independent analyses that include the full supply chain, weapons manufacturing, logistics, and contractor emissions consistently estimate 160–340 million metric tons per year — a climate footprint approaching 1% of total global emissions, coming from a single institution. And this still excludes uncounted emissions from war itself: the fires, toxic rubble, destroyed infrastructure, lost carbon sinks, and reconstruction that follow U.S. military campaigns. Globally, militaries account for at least 5.5% of greenhouse gas emissions, a conservative floor that excludes the climate damage of conflict. The United States — with over 37% of global military spending — is the largest contributor to that planetary burden. Meanwhile, the U.S. maintains 800+ military bases worldwide, each using massive quantities of fuel, generating hazardous waste, leaching toxic chemicals, and contaminating local water and soil. Communities from Okinawa to Diego Garcia to Vieques to Guam have endured poisoned aquifers, PFAS exposure, unexploded ordnance, radiation hazards, and ecological devastation — all without meaningful repair or accountability. Here at home, Camp Lejeune, Kirtland AFB, and countless other installations have left communities with cancer clusters, birth defects, and contaminated drinking water. No private corporation in America would be permitted to pollute on this scale. Yet the Pentagon is treated as untouchable. Your refusal to regulate the Department of Defense on climate grounds is indefensible. “National security” is not a justification — especially when the science is clear that unchecked U.S. militarism is itself a driver of insecurity, destabilizing global climate systems, fueling environmental injustice, and diverting resources from the real threats facing Americans: extreme weather, infrastructure collapse, food and water insecurity, and accelerating ecological breakdown. Reducing global U.S. military presence is not a liability; it is a direct benefit to our country, our communities, and countless populations worldwide who have endured generations of environmental harm for the sake of American militarism. The path forward is not mysterious. It requires political courage — not another study, not another nonbinding “strategy,” but legislation: 1. Mandate deep, immediate reductions in U.S. militarism, beginning with the closure of the vast majority of U.S. overseas bases. 2. Impose binding emissions caps, fuel-use regulations, and climate accountability requirements on the Department of Defense, including full-scope carbon reporting (Scopes 1, 2, and 3). 3. Ban the Pentagon’s most toxic practices, including the routine use of burn pits, toxic munitions, PFAS-containing firefighting foams, and unregulated waste disposal. 4. Establish environmental-impact constraints on all military operations, including naval exercises, weapons testing, and joint training that damage marine and terrestrial ecosystems. 5. Redirect a meaningful portion of the military budget toward climate mitigation, environmental restoration, and public health — the domains that actually safeguard American lives. Congress cannot continue pretending that U.S. militarism is compatible with a livable planet. It is not. The climate crisis is accelerating, and the U.S. military — the institution you fund more lavishly than any other — is actively undermining our chances of survival. Closing bases, reducing operations, and imposing environmental oversight on the Pentagon would immediately reduce global emissions, protect vulnerable communities, and strengthen true national security. You are out of excuses. Act now.