'The Secret History of the Five Eyes' intelligence alliance revealed

Richard Kerbaj’s new book uncovers the origins, tensions, and evolving global role of the Five Eyes, the world’s most powerful intelligence-sharing network.

Illustration by Carol Yepes

By Anna Fadiah and Hayu Andini

Few intelligence networks in history have operated as quietly or as effectively as the Five Eyes, the post-war alliance of the United States, United Kingdom, Australia, Canada, and New Zealand. In his ambitious and revealing book The Secret History of the Five Eyes, journalist Richard Kerbaj brings to light a story that, despite its global importance, has largely evaded public awareness. Drawing extensively from public records, political interviews, and declassified documents, Kerbaj presents a sweeping narrative of how this alliance came to be—and what challenges it now faces in an increasingly volatile geopolitical landscape.

From its roots in the desperate years of World War II to its ongoing role in counterterrorism and cyber surveillance, The Secret History of the Five Eyes details the evolution of what is arguably the most powerful intelligence-sharing network in the world. As Kerbaj makes clear, the alliance's secretive nature isn't simply for operational reasons—it also reflects deep tensions and competing interests among the member nations, particularly when it comes to their relationships with major global powers like China and Russia.

A wartime pact becomes a global surveillance juggernaut

The book opens with the formation of the alliance during the Second World War, when the U.S., U.K., and Canada first pooled their codebreaking resources in a desperate bid to defeat Nazi Germany. As the war expanded into the Pacific, Australia and New Zealand joined the effort, forming the Five Eyes network as we know it today. Their original focus—deciphering enemy communications—proved decisive in winning key battles against both Germany and Japan.

Kerbaj portrays the early years of the alliance as a time of deep cooperation, born out of necessity. Intelligence agencies shared not just encrypted messages but also personnel and infrastructure. The alliance laid the foundation for future global surveillance capabilities and established protocols for inter-agency collaboration that persist to this day.

Dividing the world: the global reach of the Five Eyes

The Five Eyes operate on an agreed-upon geographic division of labor that allows each nation to focus on specific regions. The U.S. leads in Latin America, parts of Asia, and the Middle East. The U.K. monitors Europe and Africa. Australia covers South and East Asia, while New Zealand oversees the South Pacific. Canada, meanwhile, keeps watch over the Arctic and northern China.

This division allows for a vast surveillance net, capturing everything from signal intelligence (SIGINT) and human intelligence (HUMINT) to law enforcement data from agencies like the FBI. In theory, each country has access to the findings of the others—a principle that fosters unprecedented information sharing but also creates friction when interests diverge.

Friends with benefits—or uneasy allies?

Despite their shared goals and values, Kerbaj shows that the Five Eyes are anything but a monolithic bloc. The United States, with its outsized intelligence capabilities and resources, dominates the alliance. This has bred resentment among the smaller partners, who sometimes push back against perceived American overreach.

"On the one hand, the Five Eyes is equivalent to a band of brothers and sisters drawn together by common values, language, and cause," Kerbaj writes. "On the other, the alliance is a non-binding marriage of convenience riddled with distrust, competing intelligence agendas, and a massive imbalance of power."

The alliance has faced serious internal rifts over major geopolitical crises, including the Suez Crisis, the Vietnam War, and more recently, the Trump presidency. These events have revealed fault lines that threaten the unity of the group, even as global threats demand closer cooperation than ever.

Cold War secrets and the Venona breakthrough

One of the book’s most gripping chapters covers the Cold War and the pivotal Venona Project, in which the Five Eyes successfully decrypted thousands of Soviet intelligence cables. Gene Grabeel, a former home economics teacher turned cryptographer, led the effort that exposed key Soviet spies such as Klaus Fuchs, Alger Hiss, and the Rosenbergs.

This era of intelligence success reinforced the strength of the alliance, even as each member began to develop independent policies and regional priorities. Kerbaj emphasizes how Venona not only unmasked spy networks but also solidified the Five Eyes’ place in the global intelligence hierarchy.

Shifting power dynamics in the Asia-Pacific

As China rises and global attention shifts to the Indo-Pacific, Australia’s role in the alliance has grown. Kerbaj explains how Canberra has become increasingly important to both Washington and London, especially with the launch of the AUKUS pact—a trilateral agreement involving the U.S., U.K., and Australia to help build nuclear submarines for the Australian navy.

New Zealand, by contrast, remains a more tenuous partner. Its government’s history of criticizing U.S. foreign policy has strained relations, and from Washington’s perspective, Wellington is often seen as the least reliable member of the Five Eyes. However, as China expands its influence in the South Pacific, even this alliance may take on new importance.

Canada’s curious role as the quiet partner

Canada’s position in the alliance is particularly complex. Despite being one of its founders—and contributing significantly during World War II—Canada has taken a more independent stance in recent decades. The country opposed U.S. military actions in Vietnam and Iraq, and its intelligence community has often questioned the rationale behind American-led operations.

Kerbaj notes that these tensions came to a head when Canada refused to join the 2003 invasion of Iraq. Then-Prime Minister Jean Chrétien cited a lack of credible intelligence about weapons of mass destruction, saying it was the first time Canada sat out a war involving both the U.S. and U.K.

The Trump factor and internal distrust

Kerbaj’s analysis of the Donald Trump era, written before the 2024 election cycle, focuses largely on the anxiety and skepticism Trump provoked among America’s closest allies. While the book reflects the belief—prevalent in many Western intelligence circles at the time—that Trump was either dangerously naive or willfully cozy with Vladimir Putin, it offers little follow-up on subsequent revelations about the so-called "Russia hoax."

Since then, evidence has emerged showing that the Trump-Russia narrative was rooted in a political strategy by Hillary Clinton’s campaign, and that the FBI’s surveillance of Trump’s associates raised serious legal and ethical concerns. These developments came too late for Kerbaj’s book, which stops short of covering the Biden administration’s role in realigning—or potentially fraying—the alliance.

What lies ahead for the Five Eyes?

The book concludes with a speculative chapter on the future of the Five Eyes, but by Kerbaj’s own admission, it offers more questions than answers. With Trump a potential frontrunner for re-election, and global security challenges intensifying from cyberwarfare to artificial intelligence, the alliance will likely need to adapt or risk irrelevance.

Kerbaj’s work serves as a rare window into the hidden world of international espionage. The Secret History of the Five Eyes offers a timely and provocative account of how trust, secrecy, and national interest intersect in an age of geopolitical uncertainty. Whether the alliance can withstand growing global fragmentation remains an open question—but thanks to this book, we at least understand what’s at stake.