President-elect Joe Biden is 50 days away from assuming office as commander-in-chief. He has committed to taking bold, historic action on climate change and has named climate change one of the four crises facing the United States. He has also pledged to integrate climate change into national security decision-making. This stands in stark contrast to the Trump administration, which questioned the underlying climate science and deleted “climate change” from the National Security Strategy.

At the same time, Biden may ultimately face a GOP Senate, depending on the outcome of the runoff elections in Georgia. This would strike a blow to his boldest climate ambitions—and may undermine the passage of comprehensive climate legislation. If this comes to pass, executive branch action will take on heightened importance. Regardless of any legislative effort, the Environmental Protection Agency (EPA) and other administrative agencies will likely reinstitute and strengthen Obama-era regulations to address climate change under existing legal authorities such as the Clean Air Act. But what are the president’s authorities as commander-in-chief to “combat” the national security threats posed by the climate crisis?

In addition to regulatory action under the Clean Air Act and similar authorities, Biden possesses broad constitutional authorities independent of Congress to address the climate-security impacts. I highlight four below, to include:

(1) appointing key personnel that prioritize climate change as a security issue;

(2) reducing our carbon emissions across the federal government;

(3) safeguarding critical national security infrastructure; and

(4) responding to climate-exacerbated conflicts and natural disasters at home and abroad.

Appointing Climate-Security Expertise: Personnel as Policy

First, the Constitution grants Biden broad, Article II appointment powers. His recent appointments of key personnel to national security positions—many of which do not require Senate advice and consent—highlight the growing merger between climate change’s impacts and our national security interests. For example, Biden just announced that former Secretary of State John Kerry will serve as the nation’s first special presidential envoy for climate change (the so-called “climate czar”). Kerry has unique climate experience. As a senator, he played a leadership role in the Senate’s last attempt at climate legislation in 2009. As secretary of state, he played a leadership role in the successful Paris Climate negotiations. Kerry’s new position, which does not require Senate confirmation, will also have a seat on the National Security Council—a historic first. This reflects a mature acknowledgment that climate change serves as both a “threat multiplier” and “catalyst for conflict” that requires integration across national security planning.

In addition, incoming National Security Advisor, Jake Sullivan, and Director of National Intelligence, Avril Haines, have previously highlighted the complex challenges posed by climate change in their statements and in their work. Look for their respective teams to emphasize climate change in a reimagined National Security Strategy and National Intelligence Estimate, key strategic documents that guide policy. Of course, it remains to be seen who Biden’s nominee will be to serve as secretary of defense. But one leading nominee, Michèle Flournoy, has been outspoken that the Pentagon must play a critical role in addressing climate change.

Climate Mitigation: Reducing Greenhouse Gas Emissions

Second, Biden has broad authorities to reduce the U.S. government’s greenhouse gas (GHG) emissions. He has already made clear that the United States will immediately rejoin the Paris Climate Accord. As a “sole executive agreement,” the Paris Accord does not require Senate action to re-join. Biden’s climate team can also craft bilateral and multilateral climate agreements with other nations using his foreign relations powers. Look for Biden to tap into Kerry’s deep climate expertise to breathe life into the 2015 U.S.-China international climate agreement that set the international community on a path to sign the historic Paris Climate Accord. China and the United States account for almost half of the world’s GHG emissions: the United States remains the largest historical emitter of GHG emissions and China is now the largest emitter on an annual basis. So substantive international climate progress virtually requires U.S.-China engagement.

Biden also has broad authorities, independent of Congress, to reduce the federal government’s fossil fuel dependence. As such, mitigation—or the reduction of GHG emissions—will be a focus of every executive agency to include the Department of Defense. This is significant. By institution, the U.S. military is the single largest consumer of fossil fuels in the world. And, Brown University’s Watson Institute recently estimated that the U.S. military is the 55th largest emitter in the world when ranked against countries. At its core, climate change is a complex collective action problem—the atmosphere is wholly agnostic about GHG emissions’ underlying source. The Pentagon must do its part.

The military owns a half-million buildings, occupying 27 million acres—a land mass the size of Virginia. Replacing the military’s massive fleet of older vehicles with fuel-efficient vehicles and requiring new military construction to meet Leadership in Energy and Environmental Design (LEED) standards are good places to start. Even better, the new defense secretary could leverage the Pentagon’s massive procurement power to prioritize renewable technologies that make the military more resilient. These climate mitigation efforts at DOD and across executive agencies can largely be accomplished via executive order and administrative rulemaking, something that the Obama Administration sought to implement (but was later rescinded under Trump).

While deployed, the U.S. military’s fossil fuel addiction is increasingly a liability on the battlefield—a point made by former Defense Secretary James Mattis when he led U.S. Central Command as a four-star general. Reinvigorating the Pentagon’s Office of Operational Energy, updating its energy policy, and accelerating research in dual-use technologies could be a boost on the battlefield and may even spur private-sector market growth in renewable technologies. Consider how much we rely upon the Internet and GPS today—we owe their beginning to nascent military investment in such technology.

Climate Adaptation: Protecting our National Security Infrastructure

Third, Biden has authority, at least in part independent of Congress, to take forward-looking climate adaptation steps to both (1) identify our most vulnerable national security infrastructure; and (2) invest in climate resilient infrastructure.

U.S. military bases at home and abroad are increasingly impacted by climate change. In 2019, the DOD produced a report that addressed climate change’s impacts on military bases—but this report ultimately lacked the rigor and in-depth analysis needed. The new defense secretary can correct this missed opportunity and conduct a comprehensive, risk-based analysis that identifies the climate risks to key military installations. And, the new president’s team can build upon earlier efforts to integrate long-term climate adaptation planning into existing DOD instructions and long-range planning.

Consider the example of climate change’s debilitating effects on national security infrastructure in the Kwajalein Atoll in the Marshall Islands. This hosts the Reagan Ballistic Missile Test Site test site that helps protect the United States from North Korean missiles. Climate scientists estimate that rising seas may well make parts of the Marshall Islands uninhabitable as early as 2035. As commander-in-chief, the president has broad authorities to protect the American people. He can require that climate change considerations be integrated into DOD’s building and construction. Advances in climate attribution science now showcase that climate change increases the likelihood and intensity of extreme weather. After all, the military self-insures— the Pentagon can’t call State Farm or Geico to file an insurance claim after an extreme weather event. Taxpayers foot the bill.

Most importantly, the climate risk posed to military operational readiness is difficult to quantify but is no less costly. Hurricane Michael, for example, ravaged Tyndall Air Force Base—and its fleet of F-22 fighters. Shouldn’t we begin to prepare for climate’s national security impacts in advance, in part to help minimize these costs?

Of course, Congress possesses the constitutional power of the purse and the president cannot go it alone in prioritizing climate-resilient investment. But military spending to prepare for climate change’s most harmful effects may offer a rare opportunity to find bipartisan agreement. Even the most ardent climate skeptics in Congress are happy to invest in the military bases within their jurisdiction.

Climate Response Under the President’s Commander-in-Chief Authorities

Fourth, the military must be prepared to respond to a growing list of missions as climate change destabilizes both the physical environment and geopolitics—and Biden’s constitutional authorities as commander-in-chief give him wide latitude in this regard.

Internationally, the president has comparably broader commander-in-chief powers and Article II foreign relations powers. In Justice Robert Jackson’s famous opinion analyzing the scope of the president’s commander-in-chief powers in the Korean War-era Steel Seizure case, he was skeptical of presidential national security powers when applied inward. But Jackson would “indulge the widest latitude of interpretation” when the president’s power is applied against the outside world.

Look for an increasing demand on humanitarian assistance missions as well as a renewed focus on identifying a large swath of “climate hotspots”—diverse regions of the world that most acutely feel climate change’s effects. This includes the African Sahel—an area suffering from growing food insecurity exacerbated by climate change. The United Nations has already identified climate change as contributing to a deteriorating security situation there. Another emerging climate hotspot surely includes the Arctic, which is warming two to three times the rate of the rest of the planet. Are we prepared to address a transformed Arctic shaped by new trade routes, renewed natural resource extraction, and Russian militarization?

As we look at future threats, the president can build on earlier efforts to require combatant commands to integrate climate change into their concept of operations and tap into the Pentagon’s deep expertise and culture of risk-based planning. The president can also reinvigorate the interagency process to have the best available science inform military decision-making across a growing swath of crucial climate-security questions. What is the true pace of climate change in the Arctic, and how will this impact our interests and Russia and China’s ambitions in the High North? How can Africa Command prepare for food insecurity and increasing natural resource conflicts in the African Sahel? Are we prepared for a massive climate refugee crisis in select parts of the world? By identifying, planning for, and resourcing these climate hotspots in advance, we will be better prepared to face this century’s climate-security challenges.


The disastrous U.S. response to the coronavirus crisis makes clear that we must be better prepared to address a host of non-traditional national security threats. Every few days, the coronavirus costs more American lives than were lost on 9/11. Similarly, climate change is a complex non-traditional security threat that is no less costly. Is our national security apparatus resourced and organized to meet the climate challenges this century? By focusing on these four areas —new personnel, climate mitigation, climate adaptation, and responding to the challenges posed in the climate-security century—the new commander in chief offers a fresh opportunity to answer that question.

Image: A military police officer walks near a destroyed gate in Tyndall Air Force Base, in Florida in the aftermath of Hurricane Michael on October 12, 2018 .  Photo by Brendan Smialowski/AFP via Getty Images