Jonah Lo, Ng Kang Jie and Hannah Lo

Earlier this year, The Strategy Bridge asked civilian and military students around the world to participate in our sixth annual student writing contest on the subject of strategy.

Now, we are pleased to present one of the Third Place winners from Jonah Lo and Hannah Lo from the National University of Singapore and Ng Kang Jie from Sciences Po Paris.

In the field of geopolitical analysis and strategy, models and frameworks are crucial. They inform the focus of the analyst, how to measure and evaluate the area of attention, and what to expect in the future. This process can occur consciously as part of a formal analytical procedure, or subconsciously, through the mental models that an analyst internalises. The escalation ladder is one such model. It advises an analyst to focus on how a state escalates and de-escalates against its competitors, and how to measure actions against the different escalation levels, or steps, on the ladder. From there, by examining the possible movements upwards and downwards to different steps, one can plot possible future scenarios.

Yet, this model often encounters difficulties. Often, it does not map easily onto various national contexts. Furthermore, states sometimes act in ways that do not necessarily constitute movement up or down the ladder or which appear contradictory, but seem to change the strategic dynamics of escalation. For instance, how should an escalation ladder represent the U.S. government’s response to the 2022 Russian invasion of Ukraine, where the seemingly escalatory increases in military aid to Ukraine were paired with seemingly de-escalatory unilateral commitments to not send in troops?[1]

To close these gaps, this essay proposes a new theory of specific and dynamic escalation ladders, focusing on how and why steps on the ladder are established or destroyed. Across five case studies, we will identify four variables that can lead to the creation or destruction of ladder steps—geography, capabilities, public policy rhetoric, and patterns of behaviour. We will also identify reasons why these variables differ over space and time, from individual state strategies to regional geographical phenomena. Further we will identify some of the reasons why states create and break steps in the first place. Equipped with these tools, we hope to help analysts better understand not just vertical movement along an escalation ladder, but also the evolution of the ladder itself.

However, before reconstructing the escalation ladder, we will start by deconstructing the theoretical foundations, development, and underlying arguments of the model that led to its success.

The Concept Behind the Model: Linear Escalation

Linear escalation is a prominent cornerstone of much of popular and elite strategic thought, even if it is not often articulated directly. It proposes a sequential line of actions that consists of different escalation levels in a competitive relationship, integrating all sectors of the relationship between the two powers.

This is by no means the default frame for escalation. Under the horizontal escalation concept, strategists from the Reagan administration onwards considered the possibility of segregating different theatres in the competitions between the U.S. and the U.S.S.R., permitting them to escalate, de-escalate, and maintain escalation levels where it suited them.[2]  After the Cold War, new theories emerged that considered segregating not just geographical theatres, but domains of statecraft, such as trade and climate relations.[3] Ensconced in separate silos, it would be theoretically possible to escalate competition in one geographical space or domain while maintaining or de-escalating competition elsewhere. A prominent recent case study of this is the 2021 attempt by the United States to segregate geopolitical competition with China from climate cooperation. However, this case also demonstrates the difficulty of maintaining such segregation. The Chinese refused to segregate geopolitical tension from climate cooperation, with Foreign Ministry spokesman Zhao Lijian declaring in January 2021, “Unlike flowers that can bloom in a greenhouse despite winter chill, China-U.S. cooperation in specific areas is closely linked with bilateral relations as a whole.”[4] Foreign Minister Wang Yi noted in September 2021 that “China-U.S. climate cooperation cannot be separated from the wider environment of China-U.S. relations.”[5]

Although theoretical possibilities exist for horizontal escalation, countries find it very difficult to maintain this stance. This is because governmental attitudes, goodwill and trust cannot be similarly siloed. It is difficult for the U.S. and China to trust each other and make mutual compromises on climate issues when they do not trust each other on a host of other issues. Furthermore, issues in the world are often too interrelated to easily segregate. For instance, it is hard to discuss climate cooperation without including superpower competition for technology and strategic resources. Therefore, the linear concept of escalation gives us the most utility in analysing how countries perceive and enact escalation and de-escalation.

Models of Escalation: Dichotomies, Spectrums, then Ladders

The linear escalation concept, by itself, leaves an important question unanswered. Where can one start and stop escalating or de-escalating? This would be where more specific escalation models come into play.

One could subscribe to a dichotomous model of escalation. Under this frame, states may only choose one of two options when engaging in competition—peace or war. If one were not satisfied with the former, actions to change circumstances would necessarily lead to the latter.

Yet, this seems unsatisfactory. After all, in practice states often seem able to initiate and maintain competition in the space between peaceful relations and total war. This can have substantial impacts on policy, as the war-peace dichotomy can lead policymakers to view any action that could shift a nominally peaceful status quo as an invitation towards total war. It is this dichotomous view and lack of proportion that can lead prominent figures—in Germany, for instance—to regard military aid to Kyiv during the 2022 Russian invasion of Ukraine as a path to nuclear war with Moscow.[6]

A radical alternative would be an infinitely precise spectrum of escalation. Under this frame, one could escalate or de-escalate to exactly what kind of conflict one required. However, this also seems unrealistic, especially when seeking to micro-adjust escalation down to tactical precision. One cannot merely choose to fight the war or competition one wants. The agency of opponents and contingency can cause both unexpected slipperiness and rigidities in escalation, though not necessarily as total as that imagined by the dichotomous model.

This holds policy impacts as well. During the 2022 Russian invasion of Ukraine, the proposal of establishing a no-fly zone gained political popularity in the United States, particularly outside the foreign policy sphere.[7] Framed by its proponents as a useful humanitarian mission that could be imposed without substantial risk, the proposal was nonetheless rejected by policy think tanks and NATO leaders for oversimplifying and underestimating the difficulties of keeping escalation under control in such a specific military operation that left units exposed to enemy fire.[8]

One more sophisticated exploration of the concept came through Herman Kahn’s escalation ladder model.[9] A researcher in the early nuclear age, Kahn was profoundly aware of the different gradations of war, which could range from conventional skirmishes to nuclear strikes. Along with this came an appreciation of different gradations of peace, which could range from diplomatic statements to peacetime shows of force. It thus consisted of 44 steps, ranging from a “Show of Force'' to a “Barely Nuclear War'' to a “Civilian Devastation Attack.”[10] Two major arguments underpin Kahn’s ladder.

First, linear escalation exists in steps. It is neither a spectrum where one can freely increase or decrease to whatever one desires, nor is it a fixed dichotomy where one must choose from two options. This implied that there were varying rigidities in how conflict could escalate and that strategic choices had to be made about which steps to which one should move. In essence, this was Kahn’s counterpoint to the dichotomy and spectrum models.

Second, a state’s capabilities differ across different escalation steps. This stems from the different capabilities, institutions, and technologies underpinning each step. The lower ends of an escalation ladder are carried out by diplomatic, economic, and intelligence assets, which can have different levels of capacity and effectiveness than the military and nuclear forces that occupy the higher ends. Even within steps based on military assets, operational nuances could cause large variations in capability. The U.S. could be good at fighting a nuclear conflict but bad at engaging in border skirmishes, for instance. When in a competition with an adversary, this can create situations where both competitors have parity in much of the ladder but one section is dominated by only one state’s comparative advantage. The other state would hence be disincentivised from entering this section of the ladder. This is the premise of escalation dominance, which focused on achieving advantage in high-end sections and would grow prominent in U.S. nuclear deterrence and acquisitions strategy.[11] However, it is also worth noting that Kahn’s ladder did not map out dynamics where states completely lacked credible equivalent responses to a threat, such as those between a nuclear and non-nuclear state.

The Missing Link: How to Make and Break Steps

As a generalisable model for analysing competition, Kahn’s approach proved far more explanatorily sound and intuitive than its alternatives. This gave it lasting power and impact in strategic thought and practice. It was imperfect, however. First, while providing a useful template to build upon, many of the steps were vague, with labels such as “show of force” covering everything from sponsored terrorist attacks to artillery duels. Second, many steps, particularly nuclear steps, were inapplicable to most states. Third, it lacked steps reflecting geographies or capabilities that diverge from his 1960s, Cold-War frame of reference. For instance, there is no “border skirmish” in the ladder, reflecting the lack of long, hard-to-police borders between the U.S.S.R. and the U.S. during the Cold War. This is in contrast to other dyads like that of India and Pakistan, or China and the U.S.S.R. There is also no “disinformation operation” option, reflecting that such attacks were relatively insignificant in the 1960s, in contrast with their perceived prominence in the social media age.[12]

As a result, strategists who wished to adopt Kahn’s ladder model but also apply it to various national contexts had to make changes, whether consciously or subconsciously. Unfortunately, this is where the fourth weakness of Kahn’s work emerges. Despite explaining his theoretical ladder in great detail, Kahn never explicitly discussed the circumstances in which a step would cease to exist or come into being; nor did he discuss how the steps were constructed. This meant that even conscious model modification did not have coherent theoretical foundations, leaving it somewhat arbitrary.

To address this difficulty, we will analyse a set of competitive dyads across varied geopolitical contexts to identify why and how escalation ladders differ across space and time.

The U.S. During the Cold War: How Rhetoric and Capabilities Shape Escalation (Case 1)

One intuitive reason why an escalation ladder step is broken would be that a state no longer wishes to take on the upkeep costs for the capabilities that define the step. Hence, the state can choose to defund those capabilities, causing the step to erode.

In the aftermath of World War II, popular and military exhaustion meant the United States was not willing to maintain war-level deployments in Europe.[13] As a result, the U.S. government chose to quickly demobilise much of its military.[14]

Over time, the pressures to continue this mostly demobilised state persisted, though motivations changed from immediate war exhaustion to U.S. President Eisenhower’s aversion to excessive military spending.[15] This rejection of conventional war would hence be reinforced by the Eisenhower administration’s adoption of Massive Retaliation, which publicly articulated that the U.S. found it infeasible to maintain a matching conventional military deterrent to respond to conventional Soviet incursion.[16] Instead, such attacks would be explicitly deterred by the “use of atomic weapons…against the military assets of the enemy whenever and wherever it would be of advantage to do so.”[17]

Hence, one can see that in addition to a reduction of capabilities, an articulation of policy ensured the option of conventional war remained quashed, despite being one of the most common contingencies throughout the escalation ladders of many states. This was motivated by reasons of economy in a technological and strategic context.

However, the next U.S. administration, under President Kennedy, had a new set of motivations, which in turn drove decisions to create new steps on the escalation ladder. The Kennedy administration felt Massive Retaliation was not credible in deterring small-scale Soviet incursions, and they were especially concerned about the lack of U.S. options in the event of a Soviet blockade of Berlin.[18]

Accordingly, Kennedy’s administration introduced the concept and strategy of Flexible Response.[19] This entailed an increase in U.S. conventional capabilities, especially in Europe, which would allow it to fight and hence deter small Soviet incursions with limited conventional force where nuclear threat was not credible.[20] In reality, this was implemented by modernising equipment, an increase in tactical nuclear weapons, and by improving airlift support capabilities.[21] U.S. Defence Secretary McNamara also attempted to introduce the idea of “no-cities,” where American use of nuclear weapons would be directed only against Soviet military assets—not cities—as a way of containing any nuclear conflict to below a certain threshold.[22] In effect, this created new steps on the escalation ladder that the U.S. could use to credibly deter Soviet action, granting it additional strategic flexibility.

This demonstrated that states can take creative steps on the escalation ladder in response to specific security concerns, and this can happen through both the acquisition and change of capabilities, but also through public rhetoric.

India and Pakistan: Outflanking in Escalation Dynamics (Case 2)

The making and breaking of steps is not always motivated by economic concerns or a search for strategic flexibility. Sometimes, states develop capabilities to outflank rather than match their adversaries. This approach can be more dangerous as there is no clear space for escalation to stop where both sides can find mutual satisfaction. However, it is still one that India and Pakistan pursued when they used new capabilities and rhetoric to create new steps on the escalation ladder.

Indian strategists have long been haunted by two components of the Pakistani escalation toolkit: Pakistani irregular operations at the low end of the ladder and Pakistani nuclear use at the high end. Pakistan has long had asymmetric advantages in irregular operations through its network of state-sponsored terrorists and militia.[23] However, India’s ability to escalate in response has long been constrained by the threat of Pakistani nuclear escalation.[24] In a manner reminiscent of Eisenhower’s Massive Retaliation and its rejection of conventional war, Pakistani doctrine deters Indian conventional attack through ambiguity as to Pakistan’s willingness to keep a large conventional war non-nuclear.[25]

This was sharply felt in 2001 when Pakistan-linked terrorists attacked the Indian Parliament. India initiated a mobilisation of its main forces to the Pakistani border but was unable to get into position to retaliate before Pakistan was able to mobilise its own forces in preparation.[26] Additionally, the length of time taken for India to mobilise allowed international actors to intervene on Pakistan’s behalf.[27] In response, India developed the Cold Start doctrine, which aimed to provide the military capabilities for small, limited, punitive strikes into Pakistani territory by Indian forces, while keeping the scale of the conflict small enough to deny Pakistan justification to escalate.[28] In effect, this created a Limited Strike step on the ladder designed to ensure India could retaliate against low-level aggression by Pakistan without triggering further escalation.

In 2011, Pakistan responded, developing and testing new short-range nuclear missiles such as the Nasr ballistic missile.[29] Many interpreted this as Pakistan’s attempt to construct a nuclear step lower on the ladder and, by bringing the spectre of nuclear escalation into small-scale conflicts with the Indian army, to fend off Indian attempts to fight a limited conventional war à la Cold Start.[30] Additionally, certain Pakistani policymakers made this intention explicit in interviews and statements.[31]

This case study demonstrates how states attempt outflanking strategies on the escalation ladder by exploiting comparative advantages in certain tools of statecraft and war.

The Chinese Air Force: Creating Steps Through Patterns of Behaviour (Case 3)

Thus far, the cases have addressed how escalation ladders are shaped by public rhetoric and changes in capabilities. However, these are not the only things that can shape the escalation ladder. Escalation steps can also be created by establishing patterns of behaviour.

An interesting example is found in China and the conduct of its Air Force across several conflicts. During these conflicts, despite massive land operations and fighting involving hundreds of thousands of men, Chinese air operations were heavily restricted or absent.[32] This was the case in the Korean War, the 1962 Sino-Indian War, the 1969 Sino-Soviet conflict, and the 1979 Sino-Vietnamese War.[33] During the Korean War, Chinese planes were restricted from joining Chinese land troops in operations south of the 38th parallel,[34] despite massive ongoing Air Force expansion.[35] As a result, it managed to establish a broad pattern of behaviour that made it possible to credibly threaten escalation or offer de-escalation to war or skirmish without an air element. In effect, the Chinese built new steps in their escalation ladder.

Sustaining this pattern of behaviour was not easy or straightforward. It required the Air Force to hold back from opportunities to secure Chinese objectives or save Chinese lives, as well as grant the U.S. air superiority at important junctions. This was especially galling given the immense losses taken by Chinese troops due to American air attacks.[36]

So why did China create this step? Chinese restraint in the Korean War can be linked to the desire to avoid enemy escalation against the Chinese mainland.[37] Another plausible reason is the disorganisation and limitations of its infant Air Force in the Korean War.[38] However, the reasons for Chinese limitations on airpower during subsequent skirmishes are more ambiguous. One could argue the Chinese political aims in these conflicts were too limited to pursue expensive, escalatory forms of fighting, especially since the conflicts were generally meant to be demonstrative.[39] Furthermore, during the 1960s and 1970s, funding cuts, the halting of critical training, and the severe retardation of aircraft development amid the chaos of the Cultural Revolution caused severe disruptions to air capabilities.[40] Hence, the inaction of the air arm during these conflicts could have been because Chinese leaders sought to hide their weaknesses.

This demonstrates that the creation of steps is not always a product of top-down strategy, but is sometimes due to circumstances that are out of the control of policymakers. Additionally, this shows how established patterns of behaviour can be used to create new steps on the ladder.

China and India in the Himalayas: Geographical Variables and Mutual Agreements (Case 4)

Geography is also a key driver of how escalation steps are constructed and destroyed. This is demonstrated in perhaps no better place than Sino-Indian competition in the Himalayas, where China and India have faced off since the 1960s. In this special environment, unique escalation ladders form, wherein both sides see the construction of supply infrastructure and the acclimation of troops for deployment at higher altitudes as escalatory actions. This is due to the decisive power of logistics preparation in the difficult terrain and high-altitude environment of the Himalayas, which affects projectile trajectories, eyesight, and stamina.[41] Hence, in addition to constituting steps on the ladder in of themselves, these actions create new geographical realities that  enable the construction of a new step—large, local battles. Furthermore, the environment constrains the use of heavier military assets like tanks, planes, artillery, and helicopters, and makes maintenance harder, removing multiple steps on the escalation ladder.[42] Lastly, the sparse habitation of the Himalayas reduces the military risks and nullifies civilian risks of smaller skirmishes, allowing the possibility for far more fractional and specific escalation.

The dynamics of how geographies shape escalation ladders are not limited to the Himalayas. It can also be shown prominently in competitive relationships such as the Sino-Japanese relationship, where border contestation is different from the movements of troops or tanks. Human geography should not be forgotten here either—the presence of cities, settlements and politically sensitive places can change how escalatory an act can be. Such cases can be found in Ukraine’s Donbas and Nagorno-Karabakh.

Additionally, the Sino-Indian case reiterates how steps in the escalation ladder can be created by patterns of behaviour and public rhetoric, especially in a geographical context that already slows escalation. Since 1996, agreements have limited the use of firearms in skirmishes and actions, and although troops have carried firearms during skirmishes, they have primarily fought unarmed or with improvised weapons, sometimes even with stones.[43] This facilitates further possibilities for fractional and controlled escalation.

Hence, steps on the ladder are not always created unilaterally to gain an advantage for one side or to suit one side’s change in capabilities, but can also emerge out of a mutual understanding and desire to limit and control escalation.

Israel and Iran: Increasing Complexity (Case 5)

As the world grows increasingly multipolar and complex, escalation will correspondingly become more elaborate. Escalation ladders could increasingly include the range of dynamics explored in the cases above, all occurring simultaneously. Ladder steps might rapidly change with shifting geographies, capabilities, public statements, and patterns of behaviour, possibly driven by different concurrent strategies such as cutting defence expenditures, matching adversary capabilities, or creating new asymmetrical options. An example of this is the present competition between two strategically sophisticated states—Iran and Israel.

The most obvious shifts in the Iranian-Israeli escalation ladders are those driven by capabilities—specifically Iran’s nuclear and cyber weapons programmes, largely developed to match adversary escalation ladders. Islamist Iran first developed its nuclear programme to deter weapons of mass destruction after it realized it could not deter Iraq from using chemical weapons in the 1980s Iran-Iraq War.[44] Today, its work is motivated by a desire to deter U.S. and Israeli escalation so that it can safely run its conventional, proxy-centric wars in the region.[45] Similarly, its cyber weapons programme was driven by a need to establish credible deterrents to Israeli capabilities after it was hit by the devastating Stuxnet cyber-sabotage operation in 2011.[46]

Iranian-Israeli competition has also been shaped by changes in regional human geography. After the 2011 outbreak of the Syrian civil war, the breakdown in Syrian state capacity created a special space for both Iranian and Israeli forces to operate.[47] Syria’s national borders, internationally understood and accepted, function as geographical boundaries that limit conflict, controlling escalation. In this space, Iranian troops nominally deployed to contain chaos in Syria are able to threaten Israeli security by deploying missiles and drones in range of Israel and securing an arms supply corridor to Israel’s northern enemy, Hezbollah.[48] Similarly, the Israeli Air Force is able to launch limited strikes on Iran-aligned forces at scale, deploying 70% of its pilots to hit over 950 targets in 2018-2021, which have included both Iranian proxies and commanders of the Iranian Revolutionary Guard Corps.[49]

The rise and fall of Israel’s limited strike option against Iran illustrates how past public rhetoric and patterns of behaviour cannot sustain a step once capabilities are in doubt. Limited military strikes are hard to conduct because once engagement becomes kinetic, the situation can easily escalate into conventional war. Hence, Israel needed to signal clear limitations within public rhetoric and patterns of behaviour to establish limited strikes as a distinct escalation option. This came in 1981, when Israeli Prime Minister Begin announced the Begin Doctrine, declaring, “We shall not allow any enemy to develop weapons of mass destruction turned against us” and “this attack will be a precedent for every future government in Israel.”[50]

This was backed up by a concrete pattern of action. Days before announcing the Begin Doctrine, Israel bombed the Iraqi Osirak nuclear reactor. In 2007, it bombed the Syrian Al Kabir nuclear reactor.[51] These incidents not only proved Israel’s ability to launch military strikes deep in enemy territory, but also the credibility of its limited strike options in restraining the scope of the strikes to targets pertaining to weapons of mass destruction. This demonstrates how clear and specific rhetoric, backed up by a pattern of credible action, can create steps on the escalation ladder.

However, this option of limited kinetic strikes against nuclear facilities has been decaying. Since the 2010s, Israel’s capacity for such strikes has not credibly caught up with the increased fortification and dispersion of Iranian nuclear facilities.[52] Public rhetoric and patterns of behaviour have also degraded.[53] Hence, this step is currently non-credible, pushing the Israelis towards other options such as cyber-sabotage or assassination.[54]

As such, the Iranian-Israeli case demonstrates how the shaping of escalation ladders can be tremendously complex, with concurrent strategies and dynamics at play. Furthermore, it illustrates how strategies to deal with one competitor affect escalation ladders with others, as when Iranian nuclear weapons initially developed to deter Iraq affected escalation with Israel. When one adds in the actual vertical movement states can take to escalate or de-escalate, the situation becomes even more complicated, demanding strong models to support analysis.

Conclusion

When one embraces a dynamic escalation ladder, where steps can be created and destroyed, the ladder model becomes far easier to adapt and apply to various contexts systematically. One can use Kahn’s ladder as a template, then create context-specific models accounting for differences in geography, capabilities, public rhetoric, and patterns of behaviour. Furthermore, it creates new analytical and policy opportunities.

In present geopolitical analysis, it is common to focus on movement up and down the escalation ladder. However, this frame of reference alone fails to fully explain actions wherein states are making or breaking steps. During the 2022 Russian invasion of Ukraine, U.S. President Biden publicly articulated an aversion toward conventional military intervention against Russia.[55] Those focusing only on escalation movement might merely infer that he is de-escalating tensions. However, analysts that consider the making and breaking of steps might gain more insights. They could argue that Biden was not engaging in any movement on the ladder, but rather breaking the step of direct intervention to grant him more latitude for vertical movement below that without arousing Russian fears.

Sometimes, states engage in both vertical movement and step-changing. When North Korea launches missiles into the Sea of Japan, it is both escalating tensions as well as building the capability to establish a high-end step of “nuclear war” against the United States.[56] An analyst aware of the difference would be more equipped to track and plan around both actions.

As for policy, the dynamic escalation ladder creates fresh optimism and encourages creativity when it comes to deliberately shaping the escalation ladder. Just as how the Himalayas shaped Sino-Indian engagement to create uniquely fractional steps such as unarmed skirmishing, one can make use of capabilities, public policies and patterns of behaviour to create new fractional escalation steps, keeping in mind the powerful effects of physical and human geographies. These steps can be useful when escalatory action is needed to release domestic nationalist pressures or to make strong signals that go beyond cheap talk.

This essay does not present a complete unified theory of escalation. For one, it did not thoroughly interrogate the ordering of steps. In many cases, escalation ordering is intuitive—a war without air operations is easily understood as less escalatory than a war with air operations. This essay’s analysis was built within this space. However, this becomes problematic when considering novel forms of escalation such as attacks on critical space infrastructure, and whether that would be more or less escalatory than a land skirmish, for instance.[57] This would make an excellent subject for future research.

Jonah Lo is a student at the National University of Singapore, pursuing a double major in Political Science and History. He is also the lead writer and producer of the UnderStated blog and UnderStated Audio podcast, which analyse geopolitical issues from the lens of strategic theory, history and international relations.

Ng Kang Jie is a student at Sciences Po Paris. His interests are military and imperial history, and he is a contributor to the UnderStated blog and UnderStated Audio podcast.

Hannah Lo is a recent graduate from the National University of Singapore, pursuing a double major in History and Life Sciences. She was previously published in the Mnemozine magazine of the NUS History Society. She will be pursuing a Masters in Forestry and Nature Conservation at Wageningen University.

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Header Image: Snakes & Ladders game, India, 19th century (WIkimedia)

Notes:

[1] Usher, Barbara Plett. ‘Ukraine Conflict: Why Biden Won’t Send Troops to Ukraine’. BBC News, 25 February 2022, sec. US & Canada. https://www.bbc.com/news/world-us-canada-60499385.

[2] Fitzsimmons, Michael. ‘Horizontal Escalation: An Asymmetric Approach to Russian Aggression?’ Strategic Studies Quarterly 13, no. 1 (2019): 95–133.

[3] Sweijs, Tim, Artur Usanov, and Rik Rutten. ‘CRISIS AND ESCALATION’. BACK TO THE BRINK. Hague Centre for Strategic Studies, 2016. https://www.jstor.org/stable/resrep12568.6.

[4] Wintour, Patrick. ‘U.S. Seeks Cooperation with China on Climate but Not at Any Price’. The Guardian, 20 July 2021, sec. Environment. https://www.theguardian.com/environment/2021/jul/20/us-seeks-cooperation-with-china-on-climate-but-not-at-any-price.

[5] Stanway, David. ‘U.S. Climate Envoy Kerry Urges China to Keep Politics out of Global Warming’. Reuters, 3 September 2021, sec. Asia Pacific. https://www.reuters.com/world/asia-pacific/china-holds-virtual-climate-meeting-with-us-describes-environment-policy-oasis-2021-09-02/.

[6] Jedicke, Philipp. ‘Open Letter about Weapons Deliveries to Ukraine Draws Criticism’. DW.COM, 4 May 2022. https://www.dw.com/en/open-letter-about-weapons-deliveries-to-ukraine-draws-criticism/a-61660104.

[7] Blake, Aaron. ‘Analysis | Calls Grow for a No-Fly Zone over Ukraine. Here’s What It Would Mean.’ Washington Post, 1 March 2022. https://www.washingtonpost.com/politics/2022/03/01/calls-grow-no-fly-zone-over-ukraine-heres-what-it-would-mean/.

[8] Grieco, Kelly. ‘A No-Fly Zone over Ukraine? The Case against NATO Doing It.’ Think Tank. Atlantic Council (blog), 18 March 2022. https://www.atlanticcouncil.org/blogs/new-atlanticist/a-no-fly-zone-over-ukraine-the-case-against-nato-doing-it/.; Lewis, Simon, and Ingrid Melander. ‘NATO Rejects Ukraine No-Fly Zone, Unhappy Zelenskiy Says This Means More Bombing’. Reuters, 4 March 2022, sec. Aerospace & Defense. https://www.reuters.com/business/aerospace-defense/nato-meets-ukraine-calls-no-fly-zone-hinder-russia-2022-03-04/.;Strohmeyer, Matthew, Christopher Reid, and Grace Hwang. ‘Considering the No-Fly Zone Prospects in Ukraine’. Think Tank. Center for Strategic and International Studies (blog), 30 March 2022. https://www.csis.org/analysis/considering-no-fly-zone-prospects-ukraine.

[9] Kahn, Herman. On Escalation. 1st edition. New Brunswick, N. J: Routledge, 2009.

[10] Kahn, On Escalation

[11] Fitzsimmons, Michael. ‘The False Allure of Escalation Dominance’. War on the Rocks (blog), 16 November 2017. https://warontherocks.com/2017/11/false-allure-escalation-dominance/.

[12] Paul, Christopher and Miriam Matthews, The Russian "Firehose of Falsehood" Propaganda Model: Why It Might Work and Options to Counter It. Santa Monica, CA: RAND Corporation, 2016. https://www.rand.org/pubs/perspectives/PE198.html.; Kux, Dennis. ‘SOVIET ACTIVE MEASURES AND DISINFORMATION: OVERVIEW AND ASSESSMENT’. The US Army War College Quarterly: Parameters 15, no. 1 (4 July 1985). https://doi.org/10.55540/0031-1723.1388.

[13] Bernbaum, John A., Lisle A. Rose, and Charles S. Sampson, V:509–14. Foreign Relations of the United States 1952–1954, Western European Security. Washington: United States Government Printing Office, 1983. https://history.state.gov/historicaldocuments/frus1952-54v05p1/pg_508.

[14] Barlow, Keith A. ‘Massive Retaliation’. ARMY WAR COLL CARLISLE BARRACKS PA, 8 March 1972. https://apps.dtic.mil/sti/citations/AD0764412.

[15] US National Security Council, “NSC 162/2:A Report to the National Security Council by the Executive Secretary on Basic National Security Policy” October 30th, 1953, NSC 162/2 : A Report to the National Security Council by the Executive Secretary on Basic National Security Policy (fas.org)

[16] Crowl, Philip A. ‘JOHN FOSTER DULLES: THE POLICY BEHIND THE MYTH’. Naval War College Review 27, no. 5 (1975): 8–17.

[17] Bernbaum, John A., Lisle A. Rose, and Charles S. Sampson, V:509–14. Foreign Relations of the United States 1952–1954, Western European Security. Washington: United States Government Printing Office, 1983. https://history.state.gov/historicaldocuments/frus1952-54v05p1/pg_508.

[18] Gavin, Francis J. ‘The Myth of Flexible Response: United States Strategy in Europe during the 1960s’. The International History Review 23, no. 4 (2001): 847–75.; Maloney, S.M. ‘Berlin Contingency Planning: Prelude to Flexible Response, 1958-1963’. Journal of Strategic Studies, 8 September 2010. https://doi.org/10.1080/714004038.

[19] Witteried, Peter F. ‘A Strategy of Flexible Response’. 122 Forbes Avenue,Carlisle,PA,17013-5238: US Army War College, 1972. https://apps.dtic.mil/sti/pdfs/ADA511036.pdf.

[20] Witteried, 1972, 10.

[21] Gavin, 2010.

[22] Witteried, 1972, 8.

[23] Kronstadt, K. Alan. ‘Terrorist and Other Militant Groups in Pakistan’. Congressional Report Service, 23 September 2021. https://crsreports.congress.gov/product/pdf/IF/IF11934.

[24] Tasleem, Sadia. ‘Pakistan’s Nuclear Use Doctrine’. Carnegie Endowment for International Peace. Accessed 13 May 2022. https://carnegieendowment.org/2016/06/30/pakistan-s-nuclear-use-doctrine-pub-63913.

[25] Tasleem, 2016.

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