The views expressed in this article are those of the authors and do not necessarily reflect the position of the ADF, the Department of Defence or the Australian government.

Is "Grey Zone" a helpful term, or is it just another fad term that results in military and national security professionals abrogating their required learning about war as a phenomenon?

Summary

Findings

• Grey-zone activities are coercive statecraft actions short of war.
• The term grey-zone is a successor to ‘political warfare’ and stands in contrast to the paradigms of peace/war and civil/military.
• Despite criticisms, the term grey-zone is increasingly useful and helps liberal democracies to understand, and potentially counter, coercive campaigns.
• As with earlier doctrinal developments, such as operational art, debating the term ‘grey-zone’ may obscure the importance of the underlying concept.
• The rise of grey-zone activities is an effort to bypass US conventional military dominance thereby challenging the US-led status quo.
• Grey-zone activities are mainly non-military in terms of the tactics used and the organs employed, although the campaign mindset is essentially military.
• Grey-zone campaigns make strategic gains in terms of subverting democratic practices, cultivating and subverting political elites, building and controlling key infrastructure, deterring resistance.
• Grey-zone activities benefit from an integration of the deception plan and operational plan.
• Grey-zone activities use sophisticated ‘operational art’ to layer multiple lines of operation by multiple state and non-state entities. Grey-zone campaigns are cumulative and can cause targets to ‘lose without fighting’.

Recommendations

• The Australian government should charge bodies with whole-of-government purviews with understanding grey-zone activities and directing counter grey-zone campaigns.
• The ADF should continue prioritising preparing for conventional state-on-state conflict.
• CDF/SECDEF should establish a small team dedicated to formalising Defence policy on this issue.
• The ADF should improve its capacity to counter grey-zone activities by investments in personnel, doctrine and training.
• The ADF can support whole-of government counter grey-zone activities by contributing to:
  • situational understanding through intelligence, and
  • contributing to counter grey-zone campaign planning (and training other agencies in campaign planning).
• The ADF can contribute niche capabilities to counter grey-zone activities such as:
  • covert and military forces and training,
  • training to partner nation forces, and
  • cyber and information warfare.

Scenario for Australia—1
Unopposed Fishery in the South West Pacific

By the late 2020s, over-fishing and environmental damage destroys the aquatic food chain in the South and East China Seas. Much of Asia lacks access to the protein critical to their diets. In response, Musoria initiates a campaign to gain exclusive access to the largest tuna stocks in the world—located in the South West Pacific. The campaign has initiatives throughout the region but focuses on a certain Pacific Island country that seems most vulnerable to elite cultivation. Musoria uses a regional infrastructure fund to build and gain exclusive access to key infrastructure, including a dual-use port. Musoria subverts the political system through bribery, selective awarding of local contracts and political campaign contributions. Public support is cultivated through free (but manipulated) internet satellite access as appeasement for a co-orbital manoeuvre that destroys the Australian-provided satellite services. Musoria moves to replace Australia as the security partner of choice—including increased presence of naval and air capabilities and the donation of patrol craft, small arms and secure radios.

Australian awareness of the Musorian grey-zone campaign is weakened by a lack of integration across different departments and no central body responsible for identifying or countering grey zone campaigns. Concurrently, Australia’s regional influence is degraded through reduced aid and military investment—the consequence of falling Australian GDP driven by reduced Musorian resource, tourism and education demand, combined with rampant state-sponsored cybercrime. This is then exacerbated by the removal of basing and overflight rights of the Pacific Island nation, driven by fabricated vandalism charges against RAN sailors — supported by evidence from a Musorian-funded forensic lab and exacerbated by a bot-farm driven social media campaign (supported by some Australians) that paints Australia as racist, neo-colonial and trouble-making.

After solidifying their position within the Pacific Island, Musoria becomes increasingly assertive within the region—including Australian EEZ breaches synchronised with Automated Identification System cyber-attacks and GPS-jamming to confuse the RAN response. As this escalates, efforts to erode ADF force posture includes financially incentivised denunciation of RAN operations from senior Australian commentators, protests at ADF bases and industry partners, and sabotage campaigns against ADF fuel, power generation and cyber systems. Musoria exploits the diaspora community, universities and primary industries to lobby against Australian responses to Musoria’s activities in the region. Australia’s security in the South West Pacific is eroded, the government is confused and unable to coordinate policy responses, and the ADF’s ability to respond is degraded in terms of practical readiness and public support.

Literature Review

The term ‘grey-zone’ is now widespread among national security officials. What is less common is agreement on what it means. Figure 2 illustrates the wide range of views towards the grey zone. Criticisms include that the label is poorly defined, a distortion of history, or harmful and misleading.

Ambiguity is a key strength of grey-zone campaigns. But ambiguity also makes it easy to misunderstand or dismiss the concept. Some argue creating a new grey-zone term inflates the importance of existing non-kinetic aspects of war, and/or misconstrues longstanding state actions as novel, and therefore without proven countermeasures.^[2] Another difficulty is that the grey-zone concept is discussed mainly by military thinkers, creating the false impression it is a mainly military issue. These perspectives matter because they influence governments' views and responses to coercive adversary actions.

This paper argues grey-zone is a useful lens to interpret the new ways states are applying old tactics. While many grey-zone techniques have existed for centuries — such as political subversion, psychological operations, abuse of legal process or bribery — the scale of operations and new methods of delivery, including through cyber means, add a twenty-first century twist.^[3]

Political warfare is the closest precursor term for grey-zone activities (see Annex A for related terms). The grey-zone encompasses the same wide range of coercive statecraft techniques. Its main problem arises from the plain English meanings of ‘political’ and ‘warfare’. Following a Clausewitizian view, since all warfare is political and related to the conduct of fighting in war, using ‘political’ as an adjective is redundant.^[4] Given the gravity of war and warfare, compared to the mainly non-military nature of grey-zone activities, using the term ‘warfare’ confuses more than it clarifies. ‘Grey-zone’ is admittedly metaphorical, but the metaphor aptly places it in between black and white paradigms of peace/war and civil/military.

In this paper, grey-zone is seen as being one component of hybrid warfare that includes conventional kinetic operations. Grey-zone campaigns are conducted by state actors but are likely to involve non-state entities and individuals.

Definition

Grey-zone activities are coercive statecraft actions short of war. The grey-zone is a mainly non-military domain of human activity in which states use national resources to deliberately coerce other states. States achieve grey-zone goals using multiple, apparently unrelated innocent/low attributable, mutually-supporting and synchronised statecraft techniques below the threshold of war. Grey-zone campaigns seek to exploit adversaries’ weaknesses and suppress adversaries’ response options, all the while achieving tangible national strategic aims.

“Grey-zone activities are being adopted and integrated into statecraft and are being applied in ways that challenge sovereignty and habits of cooperation. This includes challenges to the long established and mutually beneficial security partnerships Australia has with many countries, including in the Indo-Pacific.” 

“‘Grey zone’ is one of a range of terms used to describe activities designed to coerce countries in ways that seek to avoid military conflict. Examples include using para-military forces, militarisation of disputed features, exploiting influence, interference operations and the coercive use of trade and economic levers. These tactics are not new. But they are now being used in our immediate region against shared interests in security and stability. They are facilitated by technological developments including cyber warfare.”

Text Box 1: Extracts from the 2020 Defence Strategic Update Describing the Grey-Zone

Analytical Framework

Grey-zone activities are a reaction to the paradigms of peace/war and civil/military. Adversaries who use grey-zone activities are aware of the Western mindset that frames analysis and decisions around these paradigms.

Alternative paradigms consider peace/war, civil/military as spectra (Fig 3). However, this approach may obscure the threshold of war. This needs to be kept in mind when considering the risk of escalation. Applying this framework shows the range of entities and activities relevant to statecraft and the broad grey-zone of potential coercive tactics and vectors (Fig 4).

Why use grey-zone activities? The decision to use grey-zone operations arises from a fairly simple strategic calculation by the grey-zone strategist: we want a change in the behaviour of other states; we are relatively too weak militarily to achieve the change by war. We therefore seek the change in a way that does not endanger ourselves through war nor galvanise the adversary into resisting our approach. This logic is consistent with the reasoning that leads to asymmetric warfare, but goes further. Asymmetric warfare is where the weaker side seeks special advantages through using terrain or different tactics or weapons to the stronger power. Guerrilla warfare and insurgency exhibit this approach. Likewise, grey-zone operations concentrate on the advantages inherent in technique, rather than overall scale of resources. Grey-zone approaches are underpinned by the idea of ‘winning without fighting’.

Characteristics of Grey-Zone Campaigns

Based on the aforementioned analytical framework, and an analysis of the existing literature as well as the case studies examined in Annexes B-D, this paper has deduced the campaign nature of grey-zones is critically important. The power of grey-zone activities comes from skilfully arranging grey tactics in a coherent campaign that fulfils a strategic end. Grey-zone campaigns include these characteristics:

• the lack of boundaries,
• the maximal use of resources across the nation,
• the operational artistry of the campaign,
• the inherent unity of the deception plan and the operational plan,
• risk management; avoidance of escalating to war, and
• achieves strategic aims.

Lack of institutional and physical boundaries. Fluid grey-zone campaigns require strategic leadership to allow for tactics, people and entities from across society to be used in service to the campaign. This encompasses a very wide range of activities and entities. Personnel may act in their own domains (diplomats undertaking diplomacy) or they may act in other domains (military personnel facilitating intellectual property theft in cyberspace for state owned or private firms). This lack of boundaries aids in deception and maximises flexibility. The deceptiveness relies on the Western biases that tend to expect clear divisions between types of institutions. A typical Western view is to expect military branches to undertake military activities (rather than commercial ones) and civilian agencies to not undertake military actions (for instance, offshore naval base construction in disputed areas). In terms of flexibility, the lack of boundaries means a much greater ability to mix and match tactics and entities creating a wider range of options for the grey zone campaign. As a result, both new and old problems can have bespoke and unconventional solutions. Lacking physical boundaries means the campaign unfolds at home, abroad and in the cyber/informational domain.

The maximal use of resources across the nation. A fundamental reason for the existence of grey-zone operations is the unsatisfactory likely outcome of war based on inadequate military forces relative to the adversary. On the other hand, the country using grey-zone operations probably does not have overwhelming resources in any one non-military area either, such as soft power or diplomatic power. By having a boundaryless approach to grey-zone operations, relatively scarce resources in all aspects of national power can be used to best effect. For instance, having a large number of fishing vessels also affiliated to a maritime militia means resources that would already be deployed for the purpose of fishing can also generate national security effects. This is especially true when maritime militias are integrated in a campaign that includes coast guard and naval activities. Additionally, using resources from across the society can saturate the adversary’s ability to respond by using the most relevant instruments in each domain. Examples include complementing the use of naval assets to shadow naval forces with coordinated diplomacy, coercive economic and propaganda campaigns.

In WWI, nation states had to mobilise their entire economies for mass industrial warfare. This required a wide range of administrative and economic innovations to marshal resources towards the strategic end. Although grey-zone operations are much smaller in scale, they also require organisational capacity and an enabling political direction to succeed.

Prior to WWI, there was no need arising from the practice of war to distinguish the operational level of war from the tactical and the strategic. With the vast scale of that war, Soviet theorists realised the need for a conceptual framework to act as a bridge between strategy and tactics; one that was concerned with the use of forces at the campaign level. Similarly, referring to grey-zone campaigns is a way of conceiving the scale and sophistication involved in orchestrating a wide range of statecraft tactics that remains deceptive and where the various strands of the campaign are mutually supporting.

Text Box 2: Conventional Warfare Operational Art Analogy

The operational artistry of the campaign. This characteristic, more than any other, makes grey-zone operations effective and distinguishes them from traditional statecraft. In grey-zone operations, the main effort is not a single line of operation or entity, rather it is the orchestration of all elements and effects of the campaign. This is necessary to achieve the greatest gains with the least resistance. As with ‘surfaces and gaps,’ the campaign is flexible and will exploit opportunities as they arise and reduce or avoid obstacles as required. Such operational artistry requires effective strategic command. Uncertainty, confusion and decision paralysis can degrade the grey-zone exponent’s ability to control the campaign.

The inherent unity of the deception plan and the operational plan. A major part of the deception plan is the boundaryless characteristic discussed above. Additionally, incremental approaches (i.e. ‘creeping norms’), strident contrary propaganda (‘abandon Cold War thinking, adopt a win-win attitude’), the use of apparently private companies, and disaggregated activities (in time and/or space) create ambiguity. The deception is not perfect, nor is it intended to be. It merely has to disable either effective understanding or decision-making by the target country’s authorities. Democracies will be disinclined to imperil trade and risk war in the face of a murky threat picture.

Risk management; avoidance of escalating to war. The calibration of risk and the use of force will be highly controlled and directed from the centre. This is essential since the key reason grey-zone activities were chosen was to make gains without war. This means the grey-zone exponent is vulnerable to escalation by the target country, and their own C2 capability can be suppressed through surprising actions by the target country.

Achieving strategic aims. The grey-zone campaign must achieve strategic gains or it becomes merely a collection of incoherent tactics. This creates a vulnerability where an effective counter-grey zone campaign can raise the costs to the point where the effort must be suspended or abandoned.

Case studies on grey-zone campaigns by China, Russia and the US are provided in Annexes B, C and D, respectively.

Implications for the ADF

Australia has sustained losses due to adversarial grey-zone activities. This can be seen in Beijing’s use of economic coercion through barley tariffs. It can also be seen in the Chinese cultivation of Australian elites, businesses and universities. Such activities have stifled free speech and potentially weaken the nation’s preparedness to resist future coercion.

Grey-zone activities are whole-of-nation problems requiring whole-of-government solutions. Relying on the ADF to counter grey-zone activities would be a distracting drain on ADF resources and cause policy fratricide, particularly if the ADF were to over-militarise policy seeking to counter-grey zone activities.

Many Australian government and non-government entities have a role to play in countering grey-zone campaigns. As the ADF is the only organisation capable of conducting warfare, it should continue prioritising preparedness for state-on-state conventional war above counter grey-zone campaigning. Nevertheless, grey-zone activities can give the adversary significant pre-war shaping advantages that may create insurmountable obstacles to future ADF wartime strategies. The ADF cannot, therefore, neglect the grey-zone, but must be an active part of a whole-of-government understanding and response.

The ADF may face hybrid warfare. This means it may have to wage war in a context that includes grey-zone campaigns. This will complicate the political, diplomatic and informational/cyber environment of the theatre of operations, neighbouring countries, allies and the Australian continent. ADF commanders and senior staff will need a sound understanding of the grey-zone and its operational effects in competition and conflict.

Recommendations for the CDF

The recommendations below are based on the premise that the response to grey-zone activities are a whole-of-government challenge where the military will play an important, but supporting, role.

1. Advise the government to explicitly charge bodies with whole-of-government purviews with understanding grey-zone activities and directing counter grey-zone campaigns. A preliminary suggestion of appropriate bodies is:
   1. Understand: The Office of National Intelligence, as the peak analytical intelligence body, could be tasked with taking the lead in understanding the grey-zone.
   2. Coordinate and plan: The National Security Division of the Department of Prime Minister and Cabinet could be augmented with a secretariat capable of leading and coordinating counter grey-zone policy.
2. Advise and assist the government to raise public awareness of grey-zone activities, including in manifestations on Australian territory. This includes raising awareness of grey-zone activities targeted at key business, social and academic elites.
3. The ADF should maintain its focus on preparing for conventional state-on-state conflict, but develop an awareness of grey-zone activities and the potential for facing hybrid warfare. An example of how this could be achieved is specifically including grey-zone activities in the scenario for exercises and directing that all officers receive training on grey-zone activities as part of the officer training continuum.
4. Support whole-of-government counter-grey-zone activities and capabilities by contributing to understanding (through intelligence) and assisting and training officials from other government departments in campaign planning.
5. The ADF be prepared to use covert missions to counter adversary’s grey-zone activities.
6. CDF/SECDEF direct that a line of effort be established to develop an ADF counter grey-zone concept/strategy. This should include the development of joint doctrine on the grey-zone. This will ensure the ADF is positioned to counter the long-term nature of persistent grey-zone activities and avoid duplication and wasted resources. Such a team could consider:
   1. Ethical framework. The ethics of counter-grey-zone activities in light of Australian values and laws.
   2. Improving recruitment. The ADF could develop a flexible workforce by specifically targeting the recruitment of selected industries such as communications, IT and cyber for a parttime workforce. This recruitment should focus on ex-Defence members with relevant private/ public sector experience.
   3. Using secondments. The CDF could direct that secondment opportunities to relevant whole-of-government agencies be increased to provide ADF personnel with relevant skills and expose ADF officers to whole-of-government planning teams and processes.
   4. Improving training and education. The CDF could direct the Services to conduct a review of the officer training continuum and direct that awareness and planning for grey-zone activities are embedded in officer training. Review joint training curricula to recognise and practice planning for grey-zone actions. The CDF could direct that the approved sponsored tertiary/TAFE courses include studies that enable Defence planners to study areas relevant to grey-zone activities.
   5. Improve industry grey-zone awareness. Improve Defence Industry resilience to grey-zone activities. Investigate opportunities to integrate grey-zone awareness into the Defence Industry Security Program (DISP) as a means to enable defence industry to identify and report potential grey-zone actions through existing reporting mechanisms.
   6. Reviewing civil-military doctrine and training. The CDF direct the ADF Civil-Military capability be reinvigorated and prioritised, including a focus on grey-zone education and awareness. This should include reviewing civil-military doctrine, training and personnel selection.
   7. Improving cyber capabilities. The ADF should continue its investment in cyber and information warfare and develop an offensive capability.
   8. Improving collaboration with regional partners. The ADF could train and assist regional partners in information operations, possibly through rotational deployments, to identify and respond to grey-zone activities in their state. The ADF could assist regional partners to improve bilateral cyber resilience. The ADF should improve its efforts to maintain formal alumni networks with former Defence foreign students through our regional military attaché network.
   9. Building on Pacific Step-up. The ADF could increase its collective training and international engagement under the Pacific Step-Up to further develop personal relationships and trust with key military elites in the region. This should include expanding or establishing new exercises with our regional partners.

Scenario for Australia—2
Opposed Fishery in the South West Pacific with appropriate Australian whole-of-government responses

This scenario assumes most of the recommendations in this paper are incorporated into Australian government bodies including the ADF, permitting Australia to mount a counter-grey-zone campaign to deny Musoria the South West Pacific.

Australia expands the National Security Division of PM&C, authorising it to plan and coordinate a whole-of-government counter-grey zone campaign based on insights from the Office of National Intelligence. A regional counter-influence campaign includes infrastructure programs focussing on disaster resilience and aid-for-trade programs. Australia supports a program of Pacific Island institutional reform, including the establishment of an anti-foreign interference scheme supported by Australian financial intelligence capabilities. Australia also funds regional satellite communications, including free media streaming services that reinforce Australia’s regional history and commitment, and a documentary series co-produced between Four Corners and local journalists which highlights Musoria’s attempts to influence regional politics. An attempted co-orbital manoeuvre by a Musorian satellite is detected and reported by the ADF Space Situational Awareness capability, allowing the commercial provider to avoid the collision and initiate legal action through the International Telecommunications Union.

Australian corporations, underwritten by the Australian Government, invest in joint fisheries ventures with Pacific Island businesses—establishing local employment, deepening ties with the region and offsetting Musorian efforts to secure unrestricted resource access. At the same time, Australian higher education vacancies resulting from falling Musorian demand are replaced by expansion of the Australian university scholarship scheme to near neighbours—creating long-term ties with the region’s expanding middle class.

ADF contributions include upgrades of existing merchant marine bases, enabling expanded Pacific Patrol Boat operations across the region. This is supported by a tailored Common Operating Picture which is automatically fed into the Pacific Islands Maritime Fusion Centre to enhance cueing of maritime platforms. The ADF deploys Defensive Cyber Operations Teams (DCOTs) to identify, defeat and respond to intrusions into the Pacific Islands ICT infrastructure and train emerging local capabilities.

When efforts to gain basing in the region fail, Musorian state-owned trawlers attempt to create international and domestic condemnation of Australia and the ADF through operations near Australia’s EEZ, forcing an RAN response. Attempts to confuse RAN vessel locations through AIS-Spoofing and GPS jamming are mitigated by Assured-Precision Navigation and Timing systems and accurate positional data from Australia’s multi-layered surveillance systems. Concurrently, efforts to disrupt Australian bases are mitigated by effective social media counter-narrative campaigns, public exposure of the financial connections of community leaders, and a synchronised state and federal domestic security and law enforcement operation. These law-enforcement operations detect, disrupt and expose Musorian grey-zone activities – marshalling evidence Australia uses to condemn Musorian actions through the global media. Australian government institutions and private citizens understand the grey-zone competition, both inoculating Australia to much of Musoria’s campaign, and garnering support for Canberra’s counter-campaign. Musoria finds it easier and less reputationally damaging to import fish from the SWP than to exert control over an area effectively denied to them by Australia’s counter-grey zone campaign.

Conclusion

The concept of a grey-zone of coercive statecraft actions short of war is useful to Australian national security thinkers. It helps conceptualise how adversaries use the ambiguity of operating between peace and war, and civil and military organs, against target countries by employing grey-zone operational art to make strategic gains.

Failing to recognise grey-zone phenomena would leave Australia open to ‘losing without fighting’. However, a careful use of grey-zone concepts can allow effective counter-measures to be developed. Grey-zone campaigns are structured as whole-of-government undertakings and need to be understood and countered in a whole-of government way. The ADF can contribute to Australian whole-of-government efforts to understand and counter adversary grey-zone activities.

Annex A—Related Terms

Annex B—China Case Study

Beijing’s grey-zone behaviours are occurring in the context of a steadily rising China. As of 2020, China has the world’s second largest economy, second largest military budget and enough resources to spare for large-scale foreign investment. Nevertheless, China remains outmatched by absolute US military power and threatened by US diplomatic and economic power. Furthermore, China is dependant on the effective functioning of the world economy and therefore the geopolitical stability that underpins it. China wants to ‘win without fighting’ and grey-zone campaigns have worked well for Beijing in many regards, but risk prompting opposing forces to grow and cohere as a counter-balancing bloc.

Much attention has been given to the more overt and aggressive Chinese grey-zone activities that remain below threshold to spark a military response.^[5] Such actions include the creation and militarisation of artificial islands with air-strips in the Spratly Islands,^[6] the establishment of new zones of military authority with the air defence identification zone near the disputed Senkaku-Diaoyu Islands, and increased Coast Guard patrols in the East and South China Sea.^[7] Major General Zhang Zhaozhong (PLA) has referred to a ‘cabbage strategy’ for gaining influence—wrapping targeted islands with ‘…concentric layers of Chinese fishing boats, fishing administration ships, maritime enforcements ships, and warships.^[8] Where these are not useful, China can use extensive foreign investment and threats of, or actual, economic coercion supplemented with information operations against foreign citizens and governments.

Annex C—Russia Case Study

Russia’s use of the grey-zone needs to be understood in the context of ‘hybrid warfare’ where grey-zone tactics are combined with aspects of conventional warfare. Indeed, the Russians have made significant contributions to ‘hybrid warfare’ with The Nature and Content of a New Generation War and General Valery Gerasimov’s ‘Gerasimov Doctrine – New Generation Warfare’. Russian activities outlined below demonstrate that there can be distinctive differences in a grey-zone strategy between states, as the Russian strategy towards Georgia and Ukraine is more aggressive and militarised than China (at this stage).^[10] Indeed, Mazar argues that Russia’s activities are more straightforward and of such an aggressive nature, that it may be beyond ‘grey-zone’ activities, and are in fact a ‘pre-emptive military fait accompli that relies heavily on conventional military forces, sometimes deployed in clandestine and deniable ways.^[11] Seeking faits accomplis may be instead of, or as part of, a broader incremental approach. The Russian grey-zone approach is a reminder that a sufficiently determined country can wage grey-zone campaigns without China’s economic resources.

Annex D—United States Case Study

While much of the literature on grey-zone activities focus on China, Russia, Iran and North Korea, it is important to recognise that some of the techniques have arguably been used by Western states. Table D-1 shows historical examples of United States activities that may fall within the concept of grey zone activities.

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End Notes

^[1]Original artwork by Anonymous, commissioned for this report

^[2]Alessio Patalano, “When strategy is ‘hybrid’ and not ‘grey’: reviewing Chinese military and constabulary coercion at sea,” The Pacific Review 31, no. 6 (2018): 814.

^[3]Frank G. Hoffman, "Examining Complex Forms of Conflict: Gray Zone and Hybrid Challenges." Prism (Washington, D.C.) 7, no. 4 (2018): 35.

^[4]Jan Almang, “War, vagueness and hybrid war,” Defence Studies 19, no. 2 (2019): 193.

^[5]MJ Mazarr, "Mastering the grey zone: Understanding a changing era of conflict. United States Army War College Press," (2017). 87

^[6]Oliver Holmes, "China nears completion of controversial airstrip in South China Sea," The Guardian (Bangkok), 2 July 2015, https://www.theguardian.com/world/2015/jul/02/china-controversial-airstrip-south-china-sea-spratly-islands.

^[7]Chang-Liao, "China’s new foreign policy under Xi Jinping," 84; and, Michael Green, Kathleen Hicks, Zack Cooper, John Schaus, Jake Douglas, Countering coercion in maritime Asia: the the theory and practice of Grey-zone deterrence, Centre for strategic and international studies, (Lanham: Rowman & Littlefield, 2017), 10.

^[8]Green, Countering coercion in maritime Asia: the theory and practice of Grey-zone deterrence, 11.

^[9]MJ Mazarr, "Mastering the grey zone: Understanding a changing era of conflict. United States Army War College Press," (2017), 80.

^[10]MJ Mazarr, "Mastering the grey zone: Understanding a changing era of conflict. United States Army War College Press," (2017), 80.

^[11]MJ Mazarr, "Mastering the grey zone: Understanding a changing era of conflict. United States Army War College Press," (2017).