1. The beginnings
Before the current century, the American security sector paid little attention to issues of climate change. Climate change entered the national and global policy arenas not as a security concern, but primarily as a scientific endeavor. The U.S. Global Change Research Program (USGCRP), for example, had its origins in a Committee on Earth Sciences, established in 1987, within the White House Office of Science and Technology Policy (OSTP).  The Global Change Research Act of 1990 provided a mandate for this interagency committee to develop and coordinate a comprehensive research program that included issues of climate change. At the international level, the Intergovernmental Panel on Climate Change (IPCC) was created in 1988, with the support of the United States, as a joint project of the World Meteorological Organization and the United Nations Environment Program.
For the next twenty years, as IPCC worked to characterize the phenomenon of climate change, policy discussions in the U.S. centered on issues of greenhouse gas mitigation. Mitigation was not at first conceived as a security sector issue, but primarily as a concern for the energy, transportation, and economic development sectors.
Climate change entered the domain of the U.S. security sector through the side door of environmental protection. In 1993, President Bill Clinton created within the Department of Defense (DoD) an Office of the Deputy Undersecretary of Defense for Environmental Security [DUSD(ES)]. The office was primarily concerned with such environmental issues as remediation of hazardous wastes on military bases and reducing operational pollution. Clinton appointed Sherri Goodman to the post, who would become, in time, a key actor in the securitization of climate change. Seven years later, in November 2000, as the Clinton administration was coming to an end, Goodman released the first DoD document to specifically address climate change. Entitled, U.S. Department of Defense: Climate Change, Energy Efficiency, and Ozone Protection, the document stated that,
“…DoD is working to understand where and under what circumstances environmental issues may contribute to economic, political, and social instability and conflict. DoD’s international environmental cooperation efforts promote democracy, trust, and environmental stewardship while strengthening national defense. DoD works cooperatively with foreign militaries to promote regional stability and integrate environmental goals into defense operations.”
At the end of the Clinton administration, in 2001, Goodman joined CNA, a quasi-governmental think tank, where she established a Military Advisory Board, an elite group of retired three and four-star flag and general officers, to consider the security implications of climate change. The Board’s 2007 report, National Security and the Threat of Climate Change, marked the beginning of an emerging effort to securitize climate change, i.e., to recognize climate change as an existential threat. The report found that “…climate change poses a serious threat to America’s national security,” with a potential “…to disrupt our way of life and to force changes in the way we keep ourselves safe and secure.” Its finding that “Climate change acts as a threat multiplier for instability in some of the most volatile regions of the world,”  became a catchphrase for future assessments of the security implications of climate change.
2. The Obama Administration and the securitization of climate change
The CNA report recommended that the next Quadrennial Defense Review (QDR) should examine the capabilities of the U.S. military to respond to the consequences of climate change. Indeed, the next QDR, released in February 2010, became the first comprehensive American security policy document to recognize climate change as a security threat.
Following the issue of the QDR, a series of policy papers and reports expanded on the theme of climate security. These included the U.S. Navy Climate Change Roadmap which, with reference to the QDR, established a three-phased program to integrate climate change considerations into Naval plans and operations. In 2011, the Defense Science Board offered specific recommendations for improving security policy and practices in the face of climate change in a report addressed to the higher levels of the American security sector, from the White House through the Office of the Secretary of Defense and the Joint Chiefs of Staff to the geographic combatant commands. 
In 2012, the first DoD Climate Change Adaptation Roadmap presented several claims that would provide a basis for the further elaboration of U.S. security policy with respect to climate change: (1) Environmental threats constitute threats to national security; (2) There will be a growing demand for humanitarian assistance and disaster relief missions; (3) DoD needs better information and integral planning to address the threat; and (4) “Managing the national security implications of climate change will require DoD to work collaboratively, with both traditional allies and new partners.”
The security sector’s engagement with the threat of climate change had its impetus from the highest level. In November 2014, President Obama and President Xi of China met in Beijing and agreed to work together to promote what became, one year later, the Paris Accord to the U.N. Framework Convention on Climate Change (UNFCCC). Their joint announcement was in the form of a securitization claim, “The United States of America and the People’s Republic of China have a critical role to play in combating global climate change, one of the greatest threats facing humanity. The seriousness of the challenge calls upon the two sides to work constructively together for the common good.”
In February 2015, an updated National Security Strategy reflected this evolution of awareness and promulgated an official policy response to climate change as a security threat. In his cover letter, President Obama characterized the accelerating impacts of climate change as a serious challenge to national security, while calling attention to, “…the groundbreaking commitment we made with China to reduce greenhouse gas emissions – to cement an international consensus on arresting climate change.” The document identified climate change as one of eight top strategic risks to American security. 
President Obama clearly articulated the concept of climate change as an existential security threat in a speech to the Conference on Global Leadership in the Arctic, in September 2015,
“We know that human activity is changing the climate. That is beyond dispute…. But if those trend lines continue the way they are, there’s not going to be a nation on this Earth that’s not impacted negatively. People will suffer. Economies will suffer. Entire nations will find themselves under severe, severe problems. More drought; more floods; rising sea levels; greater migration; more refugees; more scarcity; more conflict.” 
In December 2015, 196 nations agreed to the Paris Accord, and on September 3, 2016, the U.S. and China formally entered into the agreement, which came into effect on November 4, 2016. The President chose not to submit the treaty to the Senate for ratification, so according to U.S. law, the Paris Accord remained an executive agreement, binding only upon the current administration.
During the second term of the Obama administration, then, climate change came to be framed as a security threat or threat multiplier, and policy and plans within the security sector reflected that understanding. This understanding was rejected and reversed under President Trump.
3. The Trump Administration and the desecuritization of climate change
Even before his campaign for the presidency, Mr. Trump endorsed climate skepticism. Between 2011 and 2015, he posted 115 tweets expressing skepticism or denial of climate change or global warming,  a perspective he maintained throughout his presidency. In October 2016, as the Paris Accord was about to go into effect, the Trump campaign called the accord a “bad deal” that would “impose enormous costs on American households through higher electricity prices and higher taxes.”
The Trump administration saw a dramatic shift in U.S. rhetoric and posture relating to climate change, as the President emphasized energy security over environmental security. The precedence of energy security over environmental security was institutionalized in the President’s Executive Order of March 28, 2017. Titled, “Promoting Energy Independence and Economic Growth,” the order sought to unburden federal regulations impacting the development of domestic energy resources with particular attention to fossil fuels. The order noted that prudent development of the nation’s energy resources was essential to geopolitical security.  It rescinded Obama’s Presidential Memorandum of September 21, 2016, Climate Change and National Security, which had declared that “Climate change poses a significant and growing threat to national security, both at home and abroad.”
On June 1, 2017, President Trump announced that the U.S. would withdraw from the Paris Climate Accord. His core argument was an economic one. He spoke of the cost to the U.S. of participating in the UNFCCC Green Climate Fund and of the “harsh economic restrictions” that the Paris Accord imposed on U.S. citizens. He characterized the Paris agreement as, “…a massive redistribution of United States wealth to other countries.” “It would once have been unthinkable that an international agreement could prevent the United States from conducting its own domestic economic affairs,” he declared, “but this is the new reality we face if we do not leave the agreement or if we do not negotiate a far better deal.” 
Trump’s statement turned on its head Obama’s argument that climate change is a security threat. There was a security threat, the new President explained, but it was not climate change. It was the global agreement to combat climate change, made by the Obama administration, that threatened American security. The Trump administration expressed these themes as policy in its December 2017, revision of the U.S. National Security Strategy.  That document notably dropped the Obama administration’s high-priority security goal to confront climate change.
These key documents of the Trump administration desecuritized climate change by treating it as less than an existential threat, and by explicitly undoing the securitizing moves of the Obama administration that led to the Paris Accord. Nonetheless, it is noteworthy that, as in the Obama administration, Trump’s actions impacting climate change policy and programs were in the form of executive actions and orders that lacked the force of law and are thus readily reversible under subsequent administrations.
President Trump appointed political leaders who agreed with and promoted his climate change policies to domestic cabinet posts including the Departments of the Interior and Energy and the Environmental Protection Agency. These agencies de-emphasized or denied the security threats of climate change and crafted their programs accordingly. It is noteworthy that these actions at the federal level were opposed and countered by several state and local governments and by many environmental NGOs.
In the Department of Defense, and in science-based agencies such as NASA and NOAA, the understanding that climate change posed a security threat held strong. For example, in testimony to the Senate Armed Services Committee in March 2017, Secretary of Defense, James Mattis said, “Climate change is impacting stability in areas of the world where our troops are operating today…. It is appropriate for the Combatant Commands to incorporate drivers of instability that impact the security environment in their areas into their planning.”
Maureen Sullivan, Deputy Assistant Secretary of Defense for Environment, Safety and Occupational Health, later observed that Mattis had set the tone on climate change for the Department from the beginning of the Trump administration. 
The major effect of White House climate change policies on the security sector were to cause its agencies to reduce the visibility and alter or avoid the vocabulary of climate change, while nonetheless pursuing science-based responses to the threat. For example, in 2017, Jeff Goodell wrote of the threat of rising sea levels to U. S. Naval Station Norfolk:
“But out on the base, nobody wants to talk directly about spending money to deal with sea-level rise, mostly because they are worried about drawing scrutiny from climate deniers in Congress who are happy to redline any expenditure with the word ‘climate’ in it. Instead, many people in the military end up talking about climate in much the way that eighth-graders talk about sex—with code words and winks and suggestive language.” 
In 2018, the National Defense Strategy (NDS) replaced the Quadrennial Defense Review. The unclassified NDS summary omitted any mention of climate change. In an advance press briefing, however, Deputy Secretary of Defense, Patrick Shanahan, explained, “We don’t specifically address climate change… There is only so much, you know, depth and breadth… it really reflects the high priorities of the department…. It doesn’t mean that it is not a priority or that it is a priority. What it says is in the national defense strategy, we don’t address it.” 
In short, leaders in the security sector sought to lower their agencies’ political visibility with respect to the term “climate change.” At the working level, however, security practitioners in defense, development and diplomatic agencies, under this cover, largely continued to address the issues of climate security and to engage with their international counterparts.
4. The Biden Administration and the resecuritization of climate change
Joseph R. Biden, Jr. (Joe Biden) made a commitment to combat climate change a key element in his presidential campaign. On Inauguration Day, January 20, the new President petitioned to re-join the Paris Accord, an action that took effect on February 19. One week after assuming office, on January 27, he issued an “Executive Order on Tackling the Climate Crisis at Home and Abroad,” that stated:
“It is the policy of my Administration that climate considerations shall be an essential element of United States foreign policy and national security. The United States will work with other countries and partners, both bilaterally and multilaterally, to put the world on a sustainable climate pathway. The United States will also move quickly to build resilience, both at home and abroad, against the impacts of climate change that are already manifest and will continue to intensify according to current trajectories.” 
The order reinstated President Obama’s September 2016 memorandum on “Climate Change and National Security” (see above). It ordered the Secretary of Defense to develop and implement a climate risk analysis and to provide an annual update on progress in incorporating the security implications of climate change into defense documents and processes. It also pledged to hold a Leaders’ Climate Summit in advance of the UNFCCC 26th Conference of the Parties, an important review of the Paris Accord scheduled for November.
In March 2021, the White House issued an Interim National Security Strategic Guidance. The document acknowledged climate change to be an existential risk. It committed the U.S. to, “…move swiftly to earn back our position of leadership in international institutions, joining with the international community to tackle the climate crisis and other shared challenges.”
Executive Branch agencies moved swiftly to implement the executive order and to adopt guidance and procedures to address climate change issues in their activities and programs. Within the security sector, Secretary of Defense Lloyd Austin immediately endorsed the President’s executive order, noting that DoD had considered climate change a threat since 2010. He committed DoD to implement the President’s orders, stating, “There is little about what the Department does to defend the American people that is not affected by climate change. It is a national security issue, and we must treat it as such.”
Secretary Austin elaborated on this theme when called upon to address the Leaders’ Summit on Climate, where he said, “Today, no nation can find lasting security without addressing the climate crisis. We face all kinds of threats in our line of work, but few of them truly deserve to be called existential. The climate crisis does.… Climate change is making the world more unsafe and we need to act.”
The resecuritization of climate change is being embraced and implemented locally by security practitioners in the field. In the Indo-Pacific region for example, in April 2021, the U.S. Indo-Pacific Command (USINDOPACOM) signed a memorandum of understanding with the University of Hawaii to collaborate in innovation and technology development to promote regional stability, sustainability, and resilience to the threat of climate change. In June, the newly-appointed USINDOPACOM commander established a Climate Change Impacts Program within the Center for Excellence for Disaster Management.
Across the United States government, then, the year 2021 has seen a resecuritization of climate change. The President appointed former Secretary of State John Kerry to be his Special Presidential Envoy for Climate, and former EPA Administrator, Gina McCarthy, to be White House National Climate Advisor. Jane Lubchenko, former Administrator of the National Oceanographic and Atmospheric Administration is serving in the new position of Deputy Director for Climate and Environment in the White House Office of Science and Technology Policy. The President replaced senior officials in EPA, Interior, and Energy, and canceled or reversed many Trump-era policies that favored fossil energy over environmental security. The depth and breadth of the new administration’s approach was summed up by Jody Freeman, Harvard University’s Archibald Cox Professor of Law and director of the School’s Environmental and Energy Law Program, as reported in The Harvard Gazette:
“’This is climate change like we’ve never known it in the federal government,…’ Freeman said the White House strategy is new because it takes a ‘whole government’ approach to climate change, enlisting not only agencies with traditional environmental oversight duties, like the EPA and the Interior Department, but every agency, such as the Defense Department, the Treasury, and the Agriculture Department, to consider how their operations may impact climate change and what can be done within their bailiwicks to fight it.”
5. Prospects and ways ahead
In the United States, as globally, there is a strong scientific consensus regarding the phenomenon of anthropogenic global warming and climate change. A political consensus, however, has yet to emerge. The issue is politically polarized between those who emphasize environmental security and the need for action to counter a long-term, existential threat; and those who emphasize energy security with vested interests in the near-term economic advantages of a fossil fuel-based economy.
Over the past twenty years, American political parties and individual and corporate stakeholders have aligned with these polar positions. Consequently, American climate policy has vacillated according to which party has held political power. Thus, at the level of the federal government, we have seen the securitization, then desecuritization, and now resecuritization of climate change. Since it is the federal government that is responsible for national security and foreign relations, U.S. climate policy has shifted with the political and contextual (i.e., scientific, social, ideological) commitments of the President. Moreover, under the last three administrations, U.S. Presidents have largely promulgated climate policy through executive orders. Thus, those policies have been and remain readily reversed or redirected by a new administration.
It is important to note that the U.S. government is not monolithic. Congress has a potential role to play in supporting or constraining the Executive Branch through the power of the purse and through the Senate’s power to approve Presidential appointments and to ratify treaties. In recent years political polarization over climate change has been reflected in the composition of Congress which, in the absence of a conflicting consensus, has generally acceded to Presidential prerogatives. This political balance is subject to change, however, if a political consensus on climate change should emerge.
Political power is also shared among federal, state, and municipal governments, which are politically diverse. Civil sector organizations including universities think tanks, and advocacy groups also influence government policies. Many state and local governments actively dissented from the climate policies of the Trump administration. For example, in 2017, California Governor Jerry Brown and New York City Mayor Michael Bloomberg launched “America’s Pledge on Climate Change.” The U.N. Climate Change Program noted that,
“Since the White House announcement of its intention to withdraw from the Paris Agreement, an unprecedented number of U.S. states, cities, businesses, and colleges and universities have reaffirmed their support for the Paris Agreement through collaborations including the “We Are Still In” declaration, the Climate Mayors coalition of cities, the U.S. Climate Alliance group of states, and others.”
State and local governments have little direct impact on international climate policy, nevertheless, they represent a political reservoir of dissent that may achieve power at the federal level in the next election.
The decentralization of governance in the U.S. system makes prediction difficult, but it is certain that under the Biden administration the U.S. is actively pursuing internal efforts and external collaborations to address the issues of climate change. All departments engaged in foreign affairs, including Defense, State, and USAID, are currently reviewing and updating their policies as per the January 27, 2021, Executive Order on Tackling the Climate Crisis at Home and Abroad. They are looking for opportunities to take a leadership position on global and regional issues of climate change. They are looking for opportunities to collaborate with partner nations to address climate mitigation, adaptation, and response, at all levels. There could not be a better time for U.S. allies and partners to reach out with proposals for cooperative ventures. Proactive American climate policies and programs will almost certainly continue for the course of the current administration and beyond if followed by a Democratic successor.
What may happen if the next administration is headed by a Republican President? The major factor will likely be that of public opinion, based upon growing personal exposure to extreme weather events and a potentially growing acceptance of the science-based consensus regarding the future course of climate change and its impacts upon their livelihoods and their children.
There is evidence that recent climate-related phenomena are already shifting public attitudes. For example, in May 2021, the Brookings Institution reported that Republican voters were ahead of their representatives in Congress in their concerns about climate change, reporting that, “A poll just before the 2020 election showed more than three-quarters of Republican voters favor government action to reduce greenhouse gas emissions.” On September 3, 2021, the New York Times reported that the year’s heatwaves, wildfires, and drought were causing Members of Congress to acknowledge the reality of anthropogenic climate change. The article noted, however, that these Republicans were typically opposing mitigation strategies based on reducing the consumption of fossil fuels, while favoring increased investments in climate adaptation, and technology innovation, such as carbon scrubbing.
It is also true that the professional civil service and military scientists and engineers provide a level of institutional inertia and continuity between administrations. Professionals in the security sector, for example, during the Trump administration, continued to address the impacts of global warming such as changes in Arctic sea ice, or sea-level rise affecting naval bases, whether or not climate change was acknowledged as a source of the phenomenon and its security threat.
Security sector activities, especially at the level of the combatant command, are more directly concerned with adaptation to climate change impacts (to promote security through resilience), and the ability to respond effectively to meet increasingly complex challenges to disaster management (to restore security and promote stability). Greenhouse gas mitigation is nonetheless important to the security sector because the extent of its success or failure will determine the future level of need for adaptation and response.
If the political trends noted in the New York Times continue, then we can expect American political polarization over the need to address climate change to decrease and to shift from a debate over WHETHER to address climate change to a debate over HOW to address it. An emerging policy emphasis on adaptation and response would increase the importance of the security sector in planning for and managing the impacts of climate change.
These four factors – increasing public concern in the face of extreme weather events, a predicted shift in the political debate from whether to address climate change to how to address it, the diversity of power centers with different perspectives on climate change in a federal system of governance, and the continuity provided by a professional civil service in the Executive Branch of the national government – support a conclusion that there will be a greater level of continuity in American climate policy whenever a political shift in the White House next occurs.
In conclusion, under the Biden administration, the U.S. is undertaking a rapid resecuritization of climate change policy at all levels. This is explicitly the case in international relations, including agencies for defense, development, and diplomacy. There is a timely opportunity therefore for the initiation of new projects and programs with partner nations to prepare for and manage the impacts of climate change. Such partnerships in the security sector will likely have cross-administration longevity, as the public experience of extreme weather events increases, and leads to some level of political agreement on the need to build resilience to the impacts of climate change.
[*] Dr. J. Scott Hauger is a former DKI APCSS faculty member and has written this research paper as an alumnus in his personal capacity. The views expressed in this article are the author’s alone, and do not necessarily reflect the official position of the DKI APCSS or the United States Government.
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U.S. Department of Defense, Climate Change, Energy, and Ozone Protection, , https://p2infohouse.org/ref/21/20958.htm
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 The author serves as Senior Advisor to the program.
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