A mundane challenge of menacing proportions? How NATO member militaries address the climate-security nexus

Climate change as a security issue

Climate change has severe impacts on security. These impacts can be approximately grouped into three subsequent sites (for more complex models, see e.g., Abrahams & Ober, 2024; Buhaug & von Uexkull, 2021). First, insecurity manifests through anthropogenic greenhouse gas emissions that reduce the share of solar radiation reflected back into space below a Holocene equilibrium. The trapped additional heat leads to a number of changes in Earth’s climate system, resulting in undesirable phenomena such as sea-level rise, heatwaves, and ecosystem losses. In turn, these phenomena increase the risks of disasters. Scholars have, however, pointed out important differences between the exposure of affected entities to climate change impacts and their vulnerability (IPCC, 2022). Individuals and communities are made vulnerable by local and global political and economic circumstances (Vogler, 2024). Therefore, as Ilan Kelman points out, “the term ‘natural disaster’ is a misnomer” (Kelman, 2024, 36).

Second, together with the crossing of other planetary boundaries (Rockström et al., 2023; Steffen et al., 2015), these direct changes impact ecosystems and human lives. ² Thereby, climate change alters or destroys ecosystems. It also poses serious risks to human health and well-being as well as to sustainable development (Adger et al., 2022; Daoudy et al., 2022), not only locally but also beyond the areas where initial impacts manifest (Franzke et al., 2022; Kivimaa, 2023).

At a third site, direct impacts can motivate human actors to respond, leading to indirect, second-order effects. Most prominently discussed are human mobility and various forms of violent conflict. But both phenomena are not straightforward consequences of climate change (Gilmore et al., 2024; Hoffmann et al., 2020; von Uexkull & Buhaug, 2021). Environmental factors can affect (mostly intranational) migration and population displacement but this relation is heavily affected by intervening societal, political, and economic factors (Koubi et al., 2022; Vestby et al., 2024). Moreover, not everyone is motivated, or capable, to leave affected regions (Nawrotzki & DeWaard, 2017; Pemberton et al., 2021). Similar caveats apply to the relation between climate change and violent conflicts. Environmental factors can affect their onset and/or dynamics (Ide, 2023b; von Uexkull & Buhaug, 2021) but, again, political and societal factors were found to be more influential (Benjaminsen & Ba, 2019; Ide et al., 2020; Wiederkehr et al., 2022).

Drawing on these dynamics, research identified how climate change renders various entities, called referent objects (Buzan et al. 1998), insecure. Climate change contributes directly to the degradation and destruction of ecosystems to the detriment of ecological security (McDonald, 2018, 2021b). As sudden- and slow-onset changes put humans into existential dangers and also impair their lives in more indirect ways, climate change creates severe risks to human security (Adger et al., 2022; Daoudy et al., 2022). Finally, a range of impacts also negatively affects assets relevant to national security, ranging from critical infrastructure over economic opportunities to state stability (Ide, 2023a).

Climate security policies and their critique: Menace or mundane?

As climate change poses risks to ecological, human, and national security, practitioners initiated a range of diverse responses aimed at protecting these referent objects from climate impacts (Brzoska, 2009; Busby, 2021; Hayes & Knox-Hayes, 2014; Krampe & Mobjörk, 2018). A wide range of policies has been linked to the label of climate security, involving actors from backgrounds as diverse as development, peace, foreign policy, environment, and conventional defense (Abrahams, 2019, 2020; Brodén Gyberg & Mobjörk, 2020; Burnett & Mach, 2021; Krampe et al., 2024; von Lucke, 2023).

Observing these activities, scholars raised two major lines of critique about climate security policies. The first line of critique characterizes some forms of climate security policies as a menace. This critique draws on securitization theory, which describes, and criticizes, the political processes involved in constructing a topic as security issue (Buzan et al., 1998; Floyd, 2019; Wæver, 1995; see also Krebs 2018) and elaborates the circumstances under which approaching climate change and its impacts as security issues might result in dangerous policies.

A core element of arguments that refer to climate security policies as a menace is the concern that these might prioritize or incentivize counterproductive means. As outlined, climate change produces insecurity to more than one referent object. These are exposed to quite different risks and threats and, accordingly, require different policies to remain protected. Therefore, the design of climate security policies is inherently political because they protect different referent objects (McDonald, 2013, 2018). This raised the concern that institutions with a narrow focus on protecting national states and their confined territories might prioritize reactive, unsustainable means (see already Barnett, 2003; Charbonneau, 2022; Deudney, 1990; von Lucke et al., 2014) and would distract from root problems such as emissions or direct climate change impacts (Daoust & Selby, 2022).

Notably, this line of critique is not unanimously rejecting approaches to climate change as security issue. Rather, authors express the hope that the conscious use of security concepts might encourage a transformation of the security sector (see also Floyd, 2015; Trombetta, 2008). In line with this thought, scholars advocated for approaches that refocus climate security on human populations (Adger et al., 2022; Daoudy et al., 2022; see also J. N. Hardt et al., 2024) or even ecosystems (McDonald, 2021b; McDonald et al., 2024), arguing that these would encourage sustainable and comprehensive climate security policies.

A second line of critique points to the rather mundane, practical difficulties in addressing climate change’s security impacts through policy. Scholars captured such mundane difficulties involved in doing climate security policy. For example, they noted, how presenting specific policy projects as different as coastal climate adaptation projects in Nigeria and the Netherlands or British foreign policy courses as security-related did neither result in accelerated project outcomes nor long-term policy support among target audiences (Oramah et al., 2022; Warner & Boas, 2019).

This mundane critique explains the limited outcomes with various features of policy and politics. Scholars describe fragmented (as opposed to integrated) governance structures at both international and national levels with differing ideas and goals for the policy problems that climate security policy is supposed to address (Abrahams, 2020; Bremberg et al., 2019; Burnett & Mach, 2021; see also Dellmuth et al., 2018; Floyd, 2015; Teicher, 2022). In turn, these incoherencies produce several practical challenges for policy formulation and implementation. Scholars observed a lack of actionable knowledge that could guide implementation (Abrahams, 2019, 2020; Brodén Gyberg & Mobjörk, 2020; Burnett & Mach, 2021) and some U.S. developmental, diplomatic, and defense practitioners interviewed for a study questioned the value added by labeling climate policies as related to security (Abrahams, 2019).

These two critiques differ in their focus, but they are not incompatible with each other. While the mundane critique focuses on practical, administrative difficulties in achieving any set climate security-related policy goals, the menace critique fears the pursuit of normatively undesirable goals through some of these policies. While different in focus, the two critiques do not form binary opposites. For example, policies can have a counterproductive (“menacing”) focus and simultaneously struggle with mundane difficulties during implementation. Similarly, efforts at reducing military emissions are likely not a menace but they may be hampered by mundane difficulties.

Military forces as climate security policy actor

Besides non-military (“civil”) institutions, militaries are increasingly initiating responses to the climate-security nexus as well. These responses are part of a wider set of “ecologically relevant military activities” (Vogler, 2024). In principle, armed forces can respond to climate-related insecurity at all three stages. They can mitigate by reducing their own emissions and enacting environmental protection (Depledge, 2023; Rajaeifar et al., 2022). Secondly, they can adapt to first-order impacts by responding to climate change’s direct symptoms through protecting their own bases and operability, even with potential synergies for civilian adaptation efforts (Teicher, 2022, 2023). Finally, militaries can be involved in attempts to provide security through climate-related operations. This prominently involves disaster response missions (Newby, 2020). But scholars worry that this could also manifest in missions aimed at obstructing migration and could condense responses to fragility to military interventions (see also Egeru, 2016; McDonald, 2018; Simangan, 2022).

Importantly, these different responses do not contribute equally to security (McDonald, 2018; Simangan, 2022). It is mitigation that prevents climate change from getting ever worse. In this regard, decarbonizing military forces is no more bizarre than regulating the use of land mines or weapons of mass destruction proliferation. Moreover, with estimates for military emissions ranging from 1% up to 5% of global emissions, decarbonizing the military sector would be no less impactful than decarbonizing air travel or the shipping industry (Parkinson & Cottrell, 2022; Rajaeifar et al., 2022). By contrast, responses at later intervention stages can only take place after significant damages have already occurred, offering limited prevention from future impacts and contributing less to human and ecological security (see also Chandler, 2020; Daoudy et al., 2022; McDonald, 2021b).

In light of these prospects, scholars have long raised concerns about military climate security policies, mostly linked to the menace line of critique. The menace line of critique expects defense bureaucracies to prioritize adaptation and climate-related operations because of their organizational self-interest (Brzoska, 2015; see also Harris, 2015; Vogler, 2023b). This would tie up resources in narrow responses to symptoms instead of contributing towards slowing environmental change or protecting vulnerable populations (Charbonneau, 2022; Daoudy et al., 2022; McDonald, 2018).

Such concerns have led to long-standing scrutiny of military responses to climate change (Barnett, 2003; Deudney, 1990) and motivated calls to transform security policy (McDonald, 2018; Trombetta, 2008). A number of studies investigated what aspects of climate change individual militaries focus on (Brzoska, 2012a; Burnett & Mach, 2021; Jayaram, 2020) and criticized them as the “climatization” of an essentially unchanged agenda or as “greenwashing” (Bigger & Neimark, 2017; Estève, 2021; Harris, 2015).

However, there is a limited understanding of the mundane processes that actually take place within defense department planning after they are mandated to conduct climate security policies. Existing studies provide important starting points (see e.g., Burnett & Mach, 2021; Estève, 2021; Jayaram, 2021). They tend, however, to focus on single cases and provide little systematic frameworks to study the practical issues involved in military forces’ efforts at implementing any climate security policies. Therefore, the mundane difficulties of defense’s climate security policies remain understudied.

This gap relates to a wider absence of up-to-date comparative analyses that study both problem framing and actual responses by different military forces and then draw conclusions related to the wider climate security literature. Seminal works predate the 2015 Paris Agreement and the 2021 NATO Climate Change and Security Action Plan (Brzoska, 2012b, 2015). Recently, two important studies focused on EU or NATO members’ military adaptation and even mitigation efforts but with limited connection to critical climate security scholarship (Amakrane & Biesbroek, 2024; Thomasen, 2025). Vice versa, critical publications have explored how defense departments frame climate and environmental change (Jayaram, 2020; Vogler, 2023b) but have not systematically assessed policy plans or implementation. Consequently, an integrating, up-to-date comparative assessment of how militaries respond to climate change is still lacking.

The remainder of this study will contribute to this goal. After briefly outlining the research design, the paper will compare the responses of NATO member forces to climate change related to mitigation, adaptation, and climate-related operations. The article thereby discusses the extent to which concerns about the menace of a militarized climate security policy have so far manifested and identifies emerging mundane difficulties in defense’s climate security efforts.

Medium-n comparative analysis

Recently, many NATO militaries have published climate-specific strategies. NATO members that are also part of the European Union are thereby responding to the requirement to develop such strategies as specified in the EEAS’ Strategic Compass (EEAS, 2022). Recent studies have identified many of them (Amakrane & Biesbroek, 2024; Thomasen, 2025). Additional strategy documents were identified manually through extensive web search, including both documents in English and the issuing countries’ domestic language. These documents were then analyzed to assess NATO militaries’ climate security-related activities related to adaptation and mitigation.

For some countries, no climate-specific defense documents were found. In these cases, the analysis checked whether the respective country published high-level security or defense strategies during recent years that commented on climate-related matters. High-level strategies are typically National Security Strategies, White Papers, Military Strategies, or Defense Strategies and were drawn from the National Security and Defence Documents Dataset (Neal & Gardner, 2024).

Based on the statements made in these strategies and in other available sources, militaries were inductively categorized, according to higher or lower degrees of communicated ambitions in mitigation and adaptation, respectively (see Table 1; Supplemental Annexes 1 and 2).

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Table 1.

Inductive categorization of militaries’ ambition levels.

Mitigation (1) Communicates overarching specific mitigation goal and details pathway (2) Communicates overarching specific mitigation goal but details no pathway (3) Communicates either only a vague overarching mitigation goal and/or reported individual measures without declaring specific overarching goal (4) No indication found

Adaptation (1) Communicates explicit, systematic adaptation agenda (2) Communicates less explicit and/or less systematic adaptation agenda (3) Communicates reluctantly but implicitly points to the agenda (4) No indication found

Case studies

To corroborate and expand the insights of this comparative approach, the analysis adds case studies on selected NATO member forces. To ensure generalizability, this approach follows the idea of a diverse case selection, selecting cases that “represent the full range of values” within a case universe (Seawright & Gerring, 2008, p. 300). To this end, the study includes case studies of NATO member forces that were assessed to have high, medium, or lower ambition levels.

Less well-studied cases were selected to generalize research beyond the comparatively well-documented cases of the United States (e.g., Burnett & Mach, 2021) and the United Kingdom (Depledge, 2023). Accordingly, case studies focused on cases that communicated higher (Canada, France), intermediate (Slovenia, Estonia), and rather emerging (Latvia) response profiles in their high-level strategy statements (see also Figure 3). Due to the limited number of previous academic studies on these cases, the case studies relied on technical environment-related documents, third-party grey literature, and interviews.

These semi-structured interviews with defense professionals were conducted to obtain additional insights from stakeholders involved in the various defense departments’ responses to climate change. This suggested a focus on knowledge-based questions “about factual information the participant holds” (King et al., 2018, p. 37) based on the expectation that the information shared would reflect an aggregation of each interviewee’s relevant day-to-day activities (von Soest, 2023).

Mitigation: Mundanely muddling through?

Most NATO member forces communicate intentions to reduce their emissions (see Figure 1; Supplemental Annex 1). These intentions, however, follow very different degrees of ambition. A group of 10 member states with comparatively high ambitions communicate overarching specific mitigation goals and provide information in varying detail on the pathways towards this long-term goal. This group consists mostly of Northern and Western European nations and Canada but does also include Estonia and Greece. Most notably, the Canadian Armed Forces declare their goal to “achieve net-zero emissions by 2050” (Government of Canada, 2023, p. 2) and the Netherlands aim for a reduction of defense-related emissions by 70% until 2050. Similarly, individual service branches such as the United Kingdom’s Air Force communicated goals to achieve net-zero for 2040. The other countries of this group announce to contribute to their respective governments’ net-zero targets (see Supplemental Annex 1).

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Figure 1.

Communicated defense-related mitigation ambitions of NATO members.

These more ambitious countries are joined by a second group of three nations, Slovenia, Sweden, and Portugal. These provide an overall intermediate level of mitigation-related ambitions. These countries communicate either a less specific overarching mitigation goal or provide only vague details about pathways towards this goal. Notably, however, Portugal published its Roteiro para a Neutralidade Carbónica 2050 Força Aérea (Air Force Roadmap to Carbon Neutrality 2050), announcing a 90% reduction of greenhouse gas (GHG) emissions by the Portuguese Air Force until 2050.

In contrast, 13 other countries communicate either only a vague overarching mitigation goal and/or reported only individual measures toward mitigation without declaring a specific overarching goal. Apart from Belgium and Luxembourg, these countries are mostly from the Mediterranean and Central/Eastern Europe. Finally, they are joined by a group of four countries that seem not to communicate any defense-related mitigation ambitions.

Corroborated through the case studies, two related insights emerge. First, the maintenance of capabilities always outweighs emission-related considerations. For example, even the comparatively ambitious Canadian Armed Forces emphasize to remain “as committed as ever to reducing our GHG emissions while remaining operationally effective” (emphasis added, National Defence Canada, 2020, p. iii). To be noted for future observation, the most recent Canadian Defense Strategy Our North, Strong and Free considerably tones down on military climate mitigation efforts in comparison to previous strategies (National Defence Canada, 2024).

Similarly, the French Climate and Defense Strategy declares a readiness to “contribute to the collective effort towards the energy transition” and the French Observatoire Défense et Climat publishes regular reports on selected activities (IRIS & DGRIS, 2024; Ministère des Armèes France, 2022, p. 8). However, the same strategy emphasizes that the French armed forces “must continue to assert the requirements of its mission to protect France’s interests and its freedom of action” (Ministère des Armèes France, 2022, p. 8) and in an interview, a French official stated that the “President of the Republic is not expecting us to reduce our carbon footprint at first” but “that we accomplish our mission” (see Supplemental Annex 3 for full quote).

The smaller Central European NATO states took similar positions. Although among the more ambitious defense departments, Estonia’s environmental strategy even states—in bold type—that “environmental and climate policy objectives will be taken into account to the extent that they do not conflict with the needs of the organisation of national defence” (Estonia, 2021, p. 3). Echoing the shock of the Russian ongoing invasion of Ukraine, officials from Latvia and Estonia emphasized how their respective military’s ability to react quickly receives overriding priority and, respectively, how the small defense administration staff is occupied with “preparing the military training fields [which] is hard and urgent and takes a lot of time” (see Supplemental Annex 3 for full quotes; see also H. Hardt, 2024).

Second, NATO member militaries developed several ways to navigate the dilemma of maintaining, and expanding, capabilities while simultaneously reducing their emissions. One is that NATO member militaries often prioritize low-hanging fruits in their mitigation strategies. This includes, for example, efforts at reducing emissions from barracks and civil logistical fleets. Greening logistical fleets and barracks, afforesting training grounds and educating military personnel on environmentally sustainable behavior has certainly its merits. However, these measures are insufficient to address militaries’ carbon problem alone, as they will not suffice to decarbonize operational energy use whose share of overall emissions is sometimes estimated to make up at least half, if not more of their emission mixes (Crawford, 2022, p. 145; Luhmann, 2021).

In addition, defense administrations seek to increase energy efficiency and to introduce sustainable fuels, particularly to address operations-related emissions. For example, the French MoD’s 2020 Defence Energy Strategy promises to make “energy transition an operational advantage” by “seeking energy efficiency […] and optimising consumption” (Ministère des Armèes France, 2020, p. 5; see Supplemental Annex 3). The other NATO forces are taking similar approaches. Canada assigned energy managers to bases and wings that “analyse energy use and identify opportunities for greater efficiency, and also work with building occupants to improve energy efficiency behaviours” (van Schaik et al., 2020, p. 58; see also Supplemental Annex 3). With regard to the Russian invasion, an Estonian interviewee even stated that “it is now more difficult to get resources for CO₂ emission reductions. I would now prioritize changing the used fuels and improve the energy efficiency of military camps” (see Supplemental Annex 3 for full quote).

The case studies also demonstrate a growing consideration of sustainable fuels in NATO member militaries’ decarbonization plans. For example, Canada specifically formulates the target to “introduce low-carbon fuels in the RCN and RCAF NSS fleets where available, affordable, compatible, and operationally feasible by 2027” (Government of Canada, 2023, p. 19). Similarly, France emphasizes in its Defence Energy Strategy to study “the use of alternative fuels (biofuels, hydrogen)” and points out that “Biodiesel is already produced and sold in the civil sector in France and abroad” (Ministère des Armèes France, 2020, p. 30). Furthermore, Slovenia is engaged in a series of research projects that focus on diverse fuel cell and hydrogen-related solutions (NATO, 2023).

Both approaches are plausible responses under the given circumstances but each carries risks of failure. The reduction of overall military emissions through increased energy efficiency is called into question because it is paralleled by a growing military energy demand. For example, the French MoD’s Energy strategy already eyes at “the possibility of integrating new weapons that are highly energy intensive (railguns, directed energy weapons, etc.).” How likely is it under these circumstances, that military institutions, mandated to do their outmost to maintain powerful forces, will not end up using the capability of moving a certain tonnage at half the energy to simply develop heavier, more capable military vehicles (see also York, 2006)? Similarly, decarbonization through the use of alternative fuels wagers on their availability—which will be dependent both on production capacities and on competing demand from the civil sector.

With such difficulties, these defense approaches to mitigation resemble an institutional muddling through that is common for institutions tasked to implement “increasingly diverse policy responsibilities” (see also Blattert et al., 2022; MacCarthaigh et al., 2023). In such cases, implementation becomes a crucial site where planners use their discretion to design policies to accommodate the diverging goals as good as possible (Cooper & Kitchener, 2018; Manna & Moffitt, 2021). The observations suggest that defense planners clearly prioritize capabilities over emission cuts. These mundane challenges create their own menace: A likely failure to achieve substantial decarbonization.

Adaptation: Does adapting to geopolitics drive mitigation?

NATO militaries also engage in adaptation to climate change. Similar to mitigation-related efforts, the degree of ambition varies across member states. Twelve defense departments communicated explicit, systematic adaptation agenda, largely overlapping with those with particular mitigation-related ambitions (see Figures 2 and 3). Beyond Canada, and Northwestern European countries, these include, Romania, Greece, and Czech Republic. Commonly, these efforts include preparations to enable military forces to remain operable in a climate-changed world. For example, the Danish Ministry of Defence calls it a “strategic objective” to “train and equip the Danish Defence to be able to operate in a security environment affected by climate change in a safe and effective manner” (Danish Ministry of Defence, 2023, p. 4). Beyond these 12 countries, Belgium, Italy, Luxembourg, the Netherlands, and Sweden are communicating somewhat less explicit or less systematic adaptation-related goals.

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Figure 2.

Communicated defense-related adaptation ambitions of NATO members.

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Figure 3.

Communicated defense-related mitigation and adaptation ambitions of NATO members.

Notably, even some security apparatuses of NATO countries that remain comparatively reluctant to communicate about climate-related defense planning, such as Poland, and Hungary, are implicitly referring to adaptation needs. In contrast to them, however, no indication was identified for a group of seven countries (see Figure 2; Supplemental Annex 2).

A comparison across high-level strategies, adaptation policy documents, and case studies revealed common justification patterns for adaptation-related efforts. Besides climate change impacts themselves, two notable arguments stand out: Geopolitical conflicts—and climate policy.

Not surprisingly, defense administrations frequently cite climate change impacts as the rationale for adaptation (see Supplemental Annex 2). The Romanian Ministry of Defence, for example, announces to adapt

the manner in which the Romanian Armed Forces carry out missions, taking into account the new operational conditions caused by climate change and environmental degradation. (Romanian Ministry of Defence, 2023, p. 19)

In a similar manner, the French Climate and Defence Strategy calls for “operational adaptation to extreme cold weather” and to “extreme heat theatres” (Ministère des Armèes France, 2022, p. 13).

But defense departments also frequently cite both geopolitical dynamics and the progressing climate policies as reasons to adapt. Besides the worry that climate change itself might be a driver of violence, several militaries pointed out that the context of growing geopolitical tensions in which climate change is manifesting called for maintaining deterrence and that this particular combination required adaptation.

The Canadian case study illustrates such concerns. Canadian policymakers state that climate change has “geopolitical implications, so it is critical that we adapt” (Government of Canada, 2023, p. iii). They worry that a melting Arctic ice would make its northern approaches increasingly accessible. In the context of the Russian invasion of Ukraine, this became particularly relevant. Western nations limited their Arctic Council participation after the Russian invasion (Government of Canada, 2022) and, a few months after the war began, the Canadian government signed off investments of more than 26 billion Canadian dollars into the North American Aerospace Defence Command (NORAD) for capabilities specifically dedicated to its high north (Government of Canada, 2022).

Curiously, a number of NATO defense administrations respond to the simultaneous concern over geopolitical conflicts and climate change with two arguments for adaptation efforts that also contribute to mitigation. For example, the Finnish Defence Forces Environmental Strategy 2021–2032 states that “the Ukrainian crisis has increased the need for independence from fossil fuels and the rapid development and introduction of renewable energy sources” (Translation by the author, Finnish Defence Forces, 2021; see also Supplemental Annex 2). Several other defense ministries communicated similar arguments. For example, the German Strategy on Defence and Climate Change states:

Given the limited availability of resources like fossil fuels, both the mobility required on the battlefield and the supply of Bundeswehr facilities must be ensured through synthetic fuels or other alternative energy sources; logistic support concepts must be adapted accordingly. (Ministry of Defence Germany, p. 24)

Secondly, defense apparatuses also regularly mention the global energy transition towards a post-fossil era as a reason to adapt by mitigation-relevant measures such as increasing energy efficiency or shifting to non-fossil energy sources. For example, the Norwegian Ministry of Defence states that “the [defense] sector must be prepared and adapt its operations to the transition from fossil fuels to renewable fuels in line with global trends” (Ministry of Defence Norway, 2022, p. 1).

Notably, such considerations extend even to some militaries whose defense administrations and wider security apparatuses have otherwise given few indications of ambitions to mitigate and to adapt. For example, Poland’s somewhat older Strategy of Development of the National Security System of the Republic of Poland 2022 warns that energy security “directly influences also the capabilities of the Polish Armed Forces” and calls for an adaptation to these circumstances through cooperation within NATO and EU on a range of mitigation-relevant efforts, such as increased energy efficiency and the development of renewable energy (Council of Ministers, Poland, 2013, p. 14). Finally, even Hungary’s Military Strategy, which orders the Hungarian military only to respond to climate change by disaster assistance and by “mitigation of the root causes of illegal mass migration” (among which the strategy then mentions climate change) emphasizes “energy storage and alternative energy sources” as capability development focus (Government of Hungary, 2021, p. 9, 10, 26).

Such adaptation efforts by militaries have in the past raised concerns that military responses to climate change might be “business as usual, just […] making everything a bit more difficult and dangerous—thus justifying bigger budgets for the same old things” (Gilman, 2022; see already Barnett, 2003; Brzoska, 2012b; Deudney, 1990). Indeed, in the case of Canada’s NORAD investments, preparations of conventional defense for an ice-free Arctic have already attracted billions of additional funds (Government of Canada, 2022). Maintaining the power to fight remains a frequent justification for military forces to adapt to climate change.

At the same time, the securitization of climate change through defense administrations has, in some cases, generated arguments for mitigation in the service of adaptation, that is, the maintenance of operability and capabilities. This suggests that the interaction between military efforts at adaptation and climate-related security is more ambiguous than previously argued. If NATO members take their own concerns about operability-related challenges seriously and pursue effective mitigation-relevant adaptation measures, then such climate security policies would not be a menace but indeed an enabler for decarbonization.

Climate-related operations: Militaries, disasters, and migration control

Initiating climate-related operations is the third and final potential military response to climate change. They include military support in disaster response and relief missions but also responses to phenomena that might be indirectly linked to climate change such as displacement or violent conflict. This latter form of engagement is the most contentious form of militaries’ climate security policies. The major concern among scholars is that such responses would come too late and rely on force, thereby rendering them reactive and unsustainable (see e.g., Charbonneau, 2022; von Lucke et al., 2014)

Assessing militaries’ preparations for these two latter lines of effort from strategy documents alone is far less straightforward than evaluating their efforts related to mitigation and adaptation. This highlights the value of qualitative assessments for individual cases (e.g., Charbonneau, 2022; Estève, 2021; Jayaram, 2021). One reason is that disaster response and stabilization operations are a long-standing task of many militaries. This means that the existence of related missions does not necessarily represent an intentional response to climate change in the same way as explicit intentions to adapt and to mitigate climate change. Moreover, reliable plans about the future scope and place of stabilization missions are both more confidential in nature and less predictable than the long-term effort to reduce emissions and to make militaries fit to operate under climate-changed conditions.

Some defense administrations, however, communicate adjustments to both disaster response and stabilization missions in light of climate change. For example, the United Kingdom’s Ministry of Defence states in its Climate Change and Sustainability Strategic Approach that the “need for Humanitarian Assistance and Disaster Relief operations will become increasingly common” and that the Kingdom’s military “will need to collaborate with new types of partners to deal with them” (Ministry of Defence United Kingdom, 2021, p. 6).

The case studies corroborate the prevalence of disaster response missions in military planning (see also Gong & Jayaram, 2023; Trias & Cook, 2023; van Schaik et al., 2020). They do, however, also reveal a substantial concern over resource constraints. Canada and France frequently deploy their militaries in response to disasters. The Canadian Armed Forces regularly support civil authorities domestically and abroad under the operational labels RENAISSANCE and LENTUS, respectively (National Defence Canada, 2023a, 2023b). The French armed forces conduct similar disaster response missions, train other forces in this capability, and conduct humanitarian operations to provide food or water supplies to their over two million citizens living in various overseas territories and extensive former colonies. A systematic monitoring of these efforts seems, however, not publicly available (see Supplemental Annex 3).

Efforts of the smaller Central European nations are more limited. Slovenia’s adaptation efforts seem to be still in their nascent phase. Slovenia’s defense department published a number of threat assessments on issues such as pandemics, wildfires, and floods in 2015 and 2016. It is telling that these documents refer to climate change only very briefly. However, after devastating forest fires in 2022, Slovenia’s Ministry of Defense purchased four new firefighting planes and intends to deploy them also in other European countries in disaster response missions. In contrast to Slovenia, an Estonian interviewee stated “they don’t feel climate change here” (see Supplemental Annex 3 for full quote). Accordingly, high-level planning documents do not call upon the Estonian armed forces to undertake disaster response, and there is also limited evidence that they are expected to play such a role. This, however, might be subject to change, given that wildfires are increasingly considered in Estonia (ERR, 2024).

In practice, these very different cases share one common feature: Military forces increasingly express concerns that their strained disaster response capacities could become overburdened (for similar debates in Australia, see McDonald, 2021a, p. 8). In Canada, military disaster responses have even become so substantial that, as early as 2018, the Canadian Chief of the Defence Staff called them “almost routine” to which the annual planning cycle had to be adjusted (cited from Leuprecht & Kasurak, 2020). In response, the Canadian Armed Forces Reserve is planned to be expanded by more than 1,500 additional personnel (National Defence Canada, 2017, p. 110).

The other cases indicated limitations in military disaster response capacities as well. The French Observatoire Défense et Climat called for “reflections on the maintenance of this capacity [to conduct humanitarian food security missions] in a context of simultaneous mobilisation […] and/or of an HADR […] as this type of operation is likely to become more frequent because of the multiplication of climatic hazards” (Observatoire Défense et Climat, 2023, p. 15).

For the smaller Central European forces, such limitations became more severe after Russia’s invasion of Ukraine. A Washington Post article quoted Slovenian Major General Robert Glavaš in 2022, describing “a dilemma [about] how to balance” the simultaneous demands on his forces emerging from the Russian invasion and domestic wildfires. He further noted that “at one point you need to decide what is important, this or that” (Birnbaum, 2022).

It seems that the Latvian government has already made this choice, pledging to donate its entire helicopter fleet to Ukraine (Latvia Public Media, 2022) ³ although it has occasionally relied on them for wildfire fighting missions (Supplemental Annex 3). This would likely reduce the Latvian armed forces’ disaster response capacity. Finally, interviewees from Estonia described how the preparation of military training areas has gained a new urgency and binds substantial resources that would otherwise be invested into responses to climate and other environmental change (Supplemental Annex 3).

Beyond disaster response, some NATO members also communicate plans to respond to potentially climate-related issues such as geostrategic shifts, displacement, and violent conflict. Again, such efforts are a controversial issue. The major concern among scholars is that such responses would come too late and rely on force, thereby rendering them reactive and unsustainable (see e.g., Charbonneau, 2022; von Lucke et al., 2014).

Indeed, some strategies suggest that militaries are preparing for climate-related operations. For example, the Danish Ministry of Defence emphasizes the need to conduct such missions in an integrated way where its military will support

an integrated approach with relevant developmental and humanitarian actors in a concrete mission area, in order to address the climate security nexus of the conflict dynamics and contribute to the stabilization of the geostrategic environment. (Danish Ministry of Defence, 2023, p. 9)

Some NATO members have begun tasking their militaries with responding to climate-related migration. This has long been a concern to critical climate security scholars (Bettini & Casaglia, 2024; Hartmann, 2014, 1998). For example, the Greek Ministry of Defence plans to increase “preparedness and surveillance measures [to] maintain security against the impacts of CC” and to conduct “joint exercises along with other allies to address new CC threats” and mentions climate-related migration in both efforts as explicit example (Ministry of National Defence Greece, 2023, pp. 65–66). Within the Greek climate strategy, responses to migration are just one among many other climate-related efforts. Other militaries communicate a much narrower focus on migration control. As mentioned before, the “mitigation of the root causes of illegal mass migration” is—besides disaster response—the only climate-related task that the aforementioned Hungarian Military Strategy explicitly assigns to its forces (Government of Hungary, 2021, p. 9).

Beyond these developments, the comparative analysis provided no indication that a prioritization among NATO’s armed forces was underway towards more frequent peacekeeping and stabilization interventions in climate-impacted contexts (see also de Coning, 2021). This seems plausible as the Russian invasion of Ukraine and growing geopolitical tensions have motivated a major reorientation among NATO members towards conventional defense efforts.

The case studies provide some additional indications. The armed forces of France, Canada, Estonia, and Slovenia signed a joint statement at the Paris Peace Forum in 2021, which briefly states that armed forces must adapt to “new types of missions” (Paris Peace Forum, 2021). The French MoD’s Observatoire Défense et Climat produces long-term scenarios on the operational implications of climate change and has been associated with an agenda of reactive militarized responses to climate impacts in the context of long-standing French geopolitical interest in the Sahel region (see also Charbonneau, 2022; Estève, 2021). Implementation, however, seems to have gone little beyond measures such as fishery patrols by French and Canadian forces in various oceans (see Supplemental Annex 3).

In addition, a French interviewee referred to challenges to France’s global supply chains (Supplemental Annex 3). Motivated by its long-standing entanglements and interventions within the Francosphere, climate change impacts have long been perceived, and institutionalized, as issues of geopolitics and security (Charbonneau, 2022; Estève, 2021). With regard to the Russian attack, the French defense planning braces to continue this long-standing strategic interest in a more challenging context (de Weck, 2023).

Where does this leave us? Just as with mitigation and adaptation, the struggles of even ambitious NATO member forces to fulfill their disaster-related tasks are, again, a quite mundane one: Governments task their subaltern institutions with more than they can implement. Policy studies have documented how democratic governments tend to overburden their institutions with ever-growing tasks in response to a diversity of political problems (Fernández-i-Marín et al., 2023; Knill et al., 2021), which results in bureaucratic overload and forces them into “organizational policy triage” (Knill et al., 2023).

To be sure, this makes the problem no less severe. It is a concerning development when the core providers of conventional state power already lack the capacity to respond to disaster-related insecurities, which are only bound to increase due to climate change. In a wider sense, these limitations add to the observation that “forces of destruction” and “modes of protection” are diverging in the contemporary “age of existential threats” (Sears, 2021, p. 2).

However, the findings also support accounts that criticize military climate-related activities as a menace. Defense strategies communicate a growing readiness for other climate-related operations, focusing on stabilization and migration control. Together with the slowly emerging indications that military-led disaster response missions are utilized as geopolitical tools (see e.g., Gong & Jayaram, 2023; Newby, 2020), these observations emphasize the risk of militarized responses to climate-related insecurity and call for close observation in the future.