The ‘Five Eyes’ Alliance: Big Brother(s)

1.0 Introduction: What is Five Eyes?

The ‘Five Eyes’ (FVEY) or the ‘UKUSA’ network is an international intelligence-sharing alliance. It consists of the United States, United Kingdom, Canada, Australia, and New Zealand. Viewed thus, ‘Five Eyes’ is a unique expression of international cooperation in signals intelligence (SIGINT) [source].

2.0 Symbols

The Five Eyes’ symbols are typically an amalgamation of the emblems belonging to each member state’s respective intelligence agencies. However, one variant includes the five national flags of each member state [see Fig. 1].

Five Eyes Intelligence Chiefs [source].

3.0 History of Five Eyes: Forging a Wartime Alliance

The genesis of Five Eyes lies in World War II-era intelligence collaboration between Britain and the US to curtail the expansionist military operations of the Axis powers across Europe and Asia. During the early postwar years, the US failed to equal Britain’s cryptanalytic capabilities. American policymakers held the UK’s Government Communications Headquarters (GCHQ) in high regard and readily accepted tutelage [source].

Recognising the other’s initial success in breaking the German Enigma Code and the Japanese Purple Code, both powers signed a highly secretive agreement in 1940. This agreement provided for a comprehensive exchange of technical communications systems and information relating to the Axis powers [source]. Bletchley Park, the home of Britain’s code-breaking apparatus, hosted a small US mission in 1941 to promote bilateral cooperation [source].

US officials provided Britain with an encryption machine for breaking Japanese codes. While Britain, in turn, reciprocated with advanced cryptographic and radio monitoring systems. Britain also provided the US with its own work on Japanese military codes, including cyphers from several countries [source], [source].

2.1 Five Eyes’ Fratricidal Divides

However, intelligence cooperation among the allies had its limits. Indeed, Britain informed US intelligence officials of their successes against Enigma and provided information about the device. Yet intelligence officials withheld Operation Ultra, the code name given to the Engima output. They also refused to share precise details related to processing and actual intelligence operations [source], [source].

Scholars like Budiansky argue that Britain regarded Ultra as a source of leverage in its intelligence relationship with the US [source]. For instance, Britain maintained its monopoly before loosening control in the wake of German technical advances in 1942 that rendered the British unable to read Atlantic U-boat traffic [source]. Despite Britain’s compromises to enable collaboration in attacking the German naval Enigma, it still sought to dominate the breaking and distribution of Enigma traffic for joint military operations. It only relented when US interests alone were threatened, such as preventing U-boat attacks off the US east coast [source].

For its part, the US was equally as cautious. The US withheld its SIGABA cypher machine due to suspicions that Britain was attempting to read US codes. These suspicions later proved legitimate. The British were, in fact, seeking to break US diplomatic codes prior to the Pearl Harbour attack in 1941 [source]. 

Churchill and Roosevelt photographed at the Atlantic Conference in 1941.
Fig.2 Roosevelt and Churchill at the Atlantic Conference in 1941.

2.1.1 Turning a New Leaf?

The impetus for further cooperation led to the inception of the 1943 British-US Communications Intelligence (BRUSA) Agreement. Two episodic events exemplified the need for a united front:

  • The beginning of joint military operations near Europe. [See: Operation Torch, the US and British invasion of French North Africa in 1942].
  • Chronic threat from German U-boat activity.

At the same time, the bilateral intelligence relationship between Canberra and Washington began to materialise. Largely owing to Australia being the headquarters of the Allied Southwest Pacific Command [source]. Most joint US and Australian intelligence activities were orphaned post-45. However, those concerned with SIGINT were re-organised as the central element in the post-war UK-US-Australian intelligence relationship [source].

2.2 From BRUSA to UKUSA

“Following the conclusion of WW2, the US SIGINT apparatus stood at the zenith of its power and prestige”

– Mathew Aid, The Secret Sentry: The Untold History of the National Security Agency [source].

US SIGINT agencies, such as the US Army’s Signal Security Agency and the Naval Communications Intelligence Organisation, comprised over 37,000 military and civilian personnel. With 37 posts and several tactical radio intelligence units operating globally [source]. However, postwar demobilisation saw the downsizing of US SIGINT capabilities with the Army and Navy units losing 80 per cent of their personnel [source]. This diminishing
capability compelled the US to seek assistance from its key wartime intelligence ally.

Similarly, Britain’s post-war economy struggled to remain solvent, compelling the government of the day to adopt harsh austerity measures. As such, the exorbitant nature of the technology underpinning SIGINT inflated costs [source]. This left Britain also looking for international partners to help share the intelligence burden.

2.2.1 An Alliance of Convenience?

Among the resources Britain could offer the US beyond its defence architecture were its territories. This included former colonies, dominions, protectorates, and mandates that constituted a ‘residual Empire’. Upon which could be established military bases and sites for the technical collection of intelligence [source].

Following Britain’s decolonisation process, a policy of peaceful disengagement allowed Britain to maintain relationships with most former colonies and protectorates. These former colonies re-organised themselves into the voluntary association known as the Commonwealth of Nations. These territories proved indispensable in the absence of space and advanced airborne collection systems during the first years of the Cold War. The US was required to construct a network of global partners to aid in the interception of Soviet communications [source]. The development of satellites and long-range reconnaissance aircraft did not obviate the necessity of ground-based installations. Viewed thus, this pooling of resources bolstered the expanding alliance’s capacity to see through the Iron Curtain.

2.3 Two Eyes to Five Eyes

In a bid to diminish any subservience to the US, Britain turned to key constituents of its ‘residual empire’. Calling upon Australia, Canada, and New Zealand, Britain inaugurated the Commonwealth SIGINT conference in 1946. The aim of this was to pool resources and create a critical mass to equalise or offset the imbalance in capabilities favouring the US [source].

Britain achieved its objective somewhat when it established a Commonwealth SIGINT Organisation (CSO) that comprised the constituent specialist intelligence agencies from:

  • The US National Security Agency (NSA)
  • The UK’s GCHQ
  • Canada’s Communications Security Establishment (CSE)
  • The Australian Signals Directorate (ASD)
  • New Zealand’s Government Communications Security Bureau (GCSB)

However, Britain was concerned with developing its international negotiations along two tracks. While negotiating multilaterally at the Commonwealth SIGINT conference, Britain entertained bilateral talks with the US, resulting in a landmark accord. Signed on 5 March 1946 by the London Signals Intelligence Board (LSIB) and US State-Army-Navy Communication Intelligence Board (STANCIB), the BRUSA Agreement formalised the postwar SIGINT alliance between the two countries.

Moreover, the Agreement’s anomalous treatment of Australia, New Zealand, and Canada meant that these countries were not signatories to what was, in effect, a bilateral Anglo-American accord. Referenced as ‘Dominions’, they enjoyed greater autonomy. However, they did not enjoy the privileges accorded to the ‘first parties’ of the agreement. Yet, in the same vein, the Agreement equally never demoted them to ‘third parties’ either.

2.4 Dominions to Signatories: The UKUSA Agreement

Canada, whose participation in the nascent SIGNT group was deemed especially crucial. According to Article Six, any arrangements STANCIB made with other dominions required LSIB approval, but the proposed collaboration between Canada and STANCIB only required ‘the views’ of LSIB [source].  This provision reflected US recognition of Canada’s relatively ‘greater’ strategic position in relation to the main Soviet threat. Further, Ottawa regarded the Agreement as evidence that it might be possible to re-shape its wartime intelligence links.

It afforded Ottawa a degree of independence rather than be subsumed into a Commonwealth apparatus led by London [source]. For instance, the bilateral signals intelligence sharing agreement with the US in 1949, known as CANUSA, reflected Canada’s distinct position and bolstered Ottawa’s independent SIGINT status [source].

In the years following, the UK and US extended and amended the Agreement to include the first Canada in 1948. With Australia and New Zealand followed closely in 1956. The merger of all parties would collectively become known as the UKUSA Agreement. The Agreement formally codified the division of spheres of responsibility for SIGINT collection between the ‘First Party’ (the US) and the Second Parties (the remaining four).

2.5 Divison of Labour and Burden-Sharing Responsibilities

Each Five Eyes member state is responsible for SIGINT across various countries, though there is often overlap and duplication.

  • The US:
    • Northern China
    • Russia
    • Africa
    • the Middle East
    • Latin America
  • The UK:
    • Europe
    • European Russia
    • Middle East
    • Africa
    • Hong Kong
  • Canada:
    • The Russian and Chinese interior
    • East Asia
    • Latin America
  • Australia
    • Southern China
    • Cambodia
    • Vietnam
    • Laos
    • Myanmar
  • New Zealand:
    • Southeast Asia
    • Maintains listening posts in South Island at Waihopai;
    • and North Island of Tangimoana

[Source], [source].

Whilst SIGINT was the bedrock of the alliance, member states established detailed Cold War co-operation in the following areas:

  • Ocean surveillance 
  • Covert action
  • Human intelligence collection (HUMINT)
  • Counterintelligence 


3.0 Organisation

3.1 Ground Relay Systems

The Five Eyes network has since evolved into a large-scale intelligence alliance with a global reach. This has been multiplied through a combination of software and hardware commitments.

When space-based satellites became prevalent in the 1960s, a series of ground stations were constructed in Five Eye member states to relay collected SIGINT. This hardware commitment proved indispensable to the maintenance and operation of systems, providing wide coverage of the Soviet Union and China during the Cold War. In Australia, Pine Gap and Nurrungar satellite bases afforded the network coverage of Soviet and Chinese military activity [source]. These facilities had the dual purpose of preserving strategic stability, and simultaneously enhancing nuclear war-fighting options for the US [source]. These facilities ensured:

  • Detection of early missile launches.
  • Detection of nuclear warheads over Soviet and Chinese territory.
  • ‘Launch-on-warning’ nuclear retaliation.
  • Flexible (re)targeting options amid nuclear exchange.
  • Monitoring of missile telemetry to verify USSR compliance with its commitments under international arms control agreements


So widely regarded were these facilities that Australian officials conceded that they would likely become prime Soviet nuclear targets. In an interview with former Deputy Secretary of the Australian Department of Defence, Andrew O’Neil confirmed that Soviet officials issued nuclear threats against the joint facilities [source]. 

3.2 Echelon Data Collection System

What began as largely SIGINT gathering transformed into the ‘Echelon’ data collection system. The scope of this was most recently revealed by the disclosures of WikiLeaks, Julian Assange, and Edward Snowden [source]. In the 1960s, Echelon primarily intercepted civilian satellites of communications based on keywords submitted by each of the Five Eyes member states. However, the proliferation of ‘Dictionaries’ – highly sophisticated computer programs- at ground relay stations has meant that communication intercepts are now categorised according to these keywords, and automatically forwarded to analysts [source].

As one might anticipate, deliberations surrounding Echelon are highly secretive. As a result, knowledge of the data collection programme has been the product of detailed scholarship and investigative reporting. Echelon is driven by the collection capabilities of the NSA and its scale is purportedly immense. Earlier Cold War SIGINT systems were primarily designed to intercept espionage, military, and diplomatic communications. By contrast, Echelon had a ‘broadband capacity’ to monitor virtually all types of electronic communications. This includes public and private sector organisations, not least individuals in almost every country [source].

Anonymous UK members photographed holding placards which read: 'I'm Julian'
Fig.6 Anonymous UK express solidarity with Julian Assange, protesting his extradition from the UK to US [source].

4.0 Five Eyes’ Intelligence Agencies

4.1 UKIC and USIC

  • UK Intelligence Community (UKIC):
    • MI5 Security Service (Internal security)
    • MI6 Secret Intelligence Service (HUMINT, foreign intelligence gathering)
    • Defence Intelligence (Analyses military intelligence)
    • Joint Intelligence Organisation (Executive Head, oversees the production of all-source intelligence assessments).
  • US Intelligence Community (USIC)
  • Central Intelligence Agency (HUMINT, foreign intelligence gathering)
  • Office of the Director of National Intelligence (Executive Head)
  • National Security Agency (SIGINT)
  • Defense Intelligence Agency (Military intelligence)

It is worth mentioning that the USIC has a total of 17 agencies, including military and law enforcement agencies which are the USIC’s most discrete.

4.2 AIC, NZIC, and Canada

  • Australian Intelligence Community (AIC)
    • Australian Signals Directorate (SIGINT)
    • Australian Security Intelligence Organisation (Internal security)
    • Australian Secret Intelligence Service (HUMINT, foreign intelligence gathering)
    • Defence Intelligence Organisation (Provides assessments of socio-political and economic developments).
    • Australian Geospatial Organisation (GEOINT)
    • Office of National Intelligence (Executive Head).
  • New Zealand Intelligence Community (NZIC)
    • Government Communications Security Bureau (SIGINT)
    • New Zealand Security Intelligence Service (Internal security, HUMINT, foreign intelligence gathering)
    • Department of the Prime Minister and the Cabinet (Executive head).
  • Canada
    • Communications Security Establishment (SIGINT)
    • Canadian Security Intelligence Service (Internal security)

Of note, Canada does not have a foreign intelligence agency dedicated to HUMINT. Although the Department of Defence and Canadian Armed Forces can gather foreign intelligence as relates to their mandate. However, the CSIS may gather only as relates to threats to Canada’s security. The sole exception to this is that CSIS may collect ‘foreign intelligence’ upon request of the ministers of national defence or foreign affairs under s16 of the CSIS Act 1984, but this is limited to individuals within Canada. Further, Canada is able to collect foreign signals intelligence via CSE [source].

5.0 Controversies

5.1 US Supremacy

Having risen to pre-eminence with its substantially greater resources, the US has supplanted Britain as the dominant intelligence power. Britain initially sought to offset this power imbalance by pooling resources with key Commonwealth countries. It used its strategically located territories with facilities to intercept Soviet-bloc communications. 

However, with the possession of increasingly superior SIGINT collection and military capabilities [source], the SIGINT gap between the US and its allies grew continually during the Cold War. By the 1980s, US security and intelligence agencies accounted for 90 per cent of the total budget and personnel of all the UKUSA agencies [source].

In addition, many accuse the US of using its vast intelligence power to shape its alliance partners’ security standards, screening criteria, and counterintelligence in a manner more consistent with its own prerogatives [source]. Should Five Eyes allies adopt policies perceived to be against US interests, they risk intelligence ‘cutoffs’ to Washington’s vast resources. Examples include:

  • The British government’s pro-European policies in the early 1970s [source].
  • New Zealand’s refusal to allow nuclear-capable warships to dock in its ports since the mid-1980s [source]. 
  • Canada’s reluctance to send naval vessels to the Gulf in 1990 [source]. 

While the US possesses superior resources, the NSA highly values its partners’ specific SIGINT contributions. This includes GCHQ’s technical capabilities and the bulk data collection and geographical coverage of the other members

5.2 Is Big Brother Watching You?

Five Eyes is often the target of public controversy, usually in relation to the disclosures of its mass surveillance programmes. Edward Snowden, former NSA analyst, alleged that FVEY intentionally spied on another’s citizens to circumvent restrictive domestic surveillance laws.

According to a leaked NSA memo, the US and UK inaugurated an agreement in 2007. The agreement allowed the NSA to analyse and retain IP addresses and phone, fax, and email records of UK citizens not suspected of any wrongdoing. Previously, the NSA minimised (‘stripped’) this data from its databases under agreed rules between the two countries. However, the NSA’s dragnet purportedly collected this information inadvertently. Meaning, it did not intend to target UK citizens as part of surveillance operations in the first instance [source].

5.3 Huawei, ZTE 5G Equipment

More recently, Five Eyes’ internal political differences have come to the fore. The most blatant is the role of the Chinese telecommunications giant, Huawei, in constructing Fifth Generation (5G) broadband cellular networks.

The US maintains that Huawei constitutes a severe threat to the Five Eyes partnership. It is highly critical of any member state that opts to rely on the tech giant’s infrastructure [source]. 

Australia has denied the possibility of Huawei in its 5G systems, subsequently banning it in 2018 [source]. New Zealand blocked the use of Huawei products by a local company building the infrastructure. Although it is yet to completely rule out the possibility [source]. Canada was previously reluctant to adopt a hard-line response. This was largely due to the politically sensitive extradition process of senior Huawei official (and daughter of the company’s founder) Meng Wanzhou in a case related to US sanctions. However, in 2022, the Canadian government also announced its plan to ban the company from its 5G networks [source]. 

5.4 US-UK Alliance in Crisis

Similarly, the UK’s position on Huawei was previously immovable. It dismissed US concerns that ‘no more than a 35 per cent’ share of the UK 5G ‘non-core’ market would still allow China to infiltrate its defence architecture. In 2020, PM Boris Johnston announced plans to completely limit Huawei’s access to the UK market [source].

Further, some postulate that the UK’s reversal was borne of a necessity to safeguard its intelligence-sharing and joint defence capabilities with the US. On May 4, the White House launched a major review of Chinese penetration of the UK’s defence architecture [source]. According to CSIS, the UK risked Five Eyes’ potential downgrade to US-UK security co-operation potentially risking:

  • The withdrawal of US RC-135 spy planes from the UK
  • A reduction in the 10,000 US military stationed in the UK
  • The deployment of the US F-35A jets on British aircraft carriers

In 2019, Gavin Williamson, former UK defence secretary, allegedly leaked secret information on Huawei amid fears that the US would reduce its defence cooperation [source]. 

6.0 The Third Parties of Five Eyes

Beyond Five Eyes’ first and second tiers, ‘third parties’ connect to the UKUSA Agreement through formal, bilateral arrangements. The NSA and respective national SIGINT agencies negotiated such arrangements in the 1950s-60s.

These ‘third parties’ cooperate with Five Eyes in two main camps:

  • NINE EYES: Five Eyes plus
    • Denmark
    • France
    • The Netherlands
    • Norway
  • FOURTEEN EYES: Nine Eyes plus
    • The Federal Republic of Germany
    • Belgium
    • Italy
    • Spain
    • Sweden

The ‘second parties’ to the original Five Eyes possess greater rights than those in the sub-level below. The US, UK, Australia, and New Zealand are generally exempt from intelligence targeting. Unless otherwise approved by the host country government. Moreover, the ‘second parties’ are able to engage in ‘essentially unqualified’ intelligence exchanges with the US. Yet, the ‘third parties’  have a looser, more limited association [source].

7.0 The Future: Five Eyes Plus Three?

Beyond the possible extension of Five Eyes, there will likely be a dramatic upheaval of defence architecture. This would allow the network to adapt to constantly evolving artificial intelligence, synthetic biology, and quantum computing. Once a technical contest over cyphers, rapid technological advancement embroils all the constituent intelligence agencies in a computing arms race.

In 2017, China announced it was creating an $11 billion national quantum laboratory, specialising in quantum hacking [source]. If successful, quantum computing would afford China the ability to decrypt asymmetric encryption algorithms. Viewed thus, it is highly likely that national variations over data retention, encryption regulations, supply chain security, disclosure of threat assessments, or even judicial oversight will arise among Five Eyes member states.

8.0 Conclusion: A New Frontier For an Old Alliance?

In sum, Five Eyes has amassed impressive intelligence-sharing capabilities over the years. However, the network will eventually have to seek out broader incorporation to ensure the maintenance of its defence architecture. Five Eyes will also need to adjust to a changing geopolitical balance and the rise of new technologies and domains.

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