Mark
Phythian
Emeritus
Professor of Politics
University
of Leicester
UK
mp249@le.ac.uk
In the autumn of 2025, the UK’s Secret Intelligence Service (SIS, aka MI6), saw the arrival of a new Chief (‘C’), Blaise Metreweli, the first woman to head the organisation. Typically for a career intelligence officer in the UK, little is known about Metreweli. We do know that after studying Anthropology at Pembroke College, Cambridge, she joined SIS in 1999 where, prior to this appointment, she was Director General Technology and Innovation. Previously, she held operational roles in the Middle East and Europe and, at some point in her career, held a Director-level role in MI5.
Since 1945, each generation has seen itself as facing a more dangerous and uncertain world than previously: just look at the language of past defence reviews or national security strategies for evidence of this, or recall James Woolsey’s February 1993 comment that, with the end of the Cold War: “We have slain a large dragon but we live now in a jungle filled with a bewildering variety of poisonous snakes. And in many ways, the dragon was easier to keep track of”. Still, there are grounds for agreeing with Prime Minister Keir Starmer’s statement in announcing Metreweli’s appointment that the UK, “is facing threats on an unprecedented scale”, and that, “the work of our intelligence services has never been more vital.” Given the nature of these threats, Metreweli’s CV explains her appointment; first and foremost, the expertise in technology, but also the operational roles in the Middle East and Europe, and cross-community professional experience – increasingly important in a world where old distinctions between ‘foreign’ and ‘domestic’ threats have given way to a more complex, ‘intermestic’, national security agenda.
Her predecessor as Chief of SIS, Sir Richard Moore, gave what amounted to his valedictory speech in Istanbul in September 2025. This was part of a significant trend in UK intelligence whereby agency heads deliver public speeches outlining the work and priorities of their agencies and assessment of the threat landscape. These are particularly welcome given the absence of a formal, published, annual threat assessment (as in the United States), or public evidence sessions in front of the UK’s legislative intelligence oversight body, the Intelligence and Security Committee of Parliament, whose relationship with the agencies and executive branch has been strained over recent years. Moore himself gave a number of these speeches during his tenure, but it was his predecessor, Sir Alex Younger who broke significant ground with a speech at St Andrews University in December 2018, in which he talked in terms of the “fourth generation espionage” required to tackle the “degree of interconnectedness between nations, peoples and systems today, the ubiquitous nature of information, and the exponential pace of technological change, [which] are making the world dramatically more complicated.”
At the same time, the Director of GCHQ, Jeremy Fleming, was giving significant and reflective speeches on the work of his organisation and the threat environment it faced: for example, discussing the concept of a “Cyber Power” and speaking openly about “offensive cyber” operations. Principles of accountability and ethical conduct tended to be emphasised in these speeches, reflecting the immediate post-Snowden context and need to rebuild trust and so assert the legitimacy of the activities and approaches being outlined. In a subsequent speech, the October 2022 RUSI Annual Security Lecture, Fleming focused on, “what I believe is the national security issue that will define our future”, asking: “If China is the question, then what is the answer?”. For Fleming, “when it comes to technology, the politically motivated actions of the Chinese state is an increasingly urgent problem we have to acknowledge and address. That’s because it’s changing the definition of national security into a much broader concept. Technology has become not just an area for opportunity, for competition and for collaboration, it’s become a battleground for control, values and influence.”
Moore’s September 2025 Istanbul speech focused on the threat and challenges posed by Russia. He also outlined a new way in which the traditional human dimension of the craft of spying was being supported by technology. Moore set out how, “those men and women in Russia who have truths to share and the courage to share them” could now, “reach us securely online via our new dark web portal, Silent Courier. Our virtual front door harnesses the anonymity of the dark web so that anyone, anywhere in the world can make secure contact with MI6. So, contact us today via Silent Courier and choose a different future for yourself, for your family and for your country.”
At the same time, Moore discussed SIS’s other three priorities – China, Iran, and counter terrorism – making it clear that Silent Courier was not simply a resource to be considered by those inside Russia. As Moore explained: “Anyone, anywhere in the world with access to sensitive information relating to terrorism or hostile intelligence activity, can use the new portal to contact MI6.” The challenges posed by China, as a rising global power, were more complex, and Moore’s depiction of a country that “in many respects straddles that dichotomy of opportunity and threat” captures well Western state dilemmas. As he put it: “We, in the UK, want a respectful and constructive relationship with China. But China needs to stick to the established rules of engagement and non-interference that it publicly promotes. I hear the concerns of my colleague, Director MI5 Sir Ken McCallum, about Chinese interference in the UK; and we, in the UK, will be robust in defending our freedoms, our way of life and our economic security.”
Yet, that same month, a political row broke out in the UK after the Crown Prosecution Service (CPS) abandoned the prosecution of two men, one of whom was a former parliamentary researcher, charged under the Official Secrets Act with passing information to an “enemy” (both men denied the charges). Reportedly, the CPS dropped the case because it could not secure a government witness statement to confirm that China was indeed “a threat to the national security of the UK”, as per the requirement of the legislation. Was this due to government back-tracking and a preference for labelling China a “challenge” but not an “enemy”, as it sought to develop UK-China trade relations? Or was it a decision reached by the CPS without any governmental pressure? A high-profile blame game ensued. Either way, the wording of the relevant legislation at the time was not helpful and did not reflect the complex world of contemporary national security. That China did pose a threat to the UK was a well-established reality for MI5, SIS, and GCHQ – as shown above.
At the same time, developments over recent months have begged questions not just of when, in the contemporary world of big power competition underpinned by ‘deniable’ conduct in the cyber realm, a foreign state represents enough of a challenge or threat to be labelled an ‘enemy’. Questions of what constitutes a ‘friend’ in intelligence, security and alliance terms have also been raised: for example, by the implications of the Trump Administration’s ‘America First’ approach for Five Eyes co-operation and intelligence-sharing (for example, with regard to the Russo-Ukrainian War), and by claims that Hungary has operated a spy network in Brussels, casting doubt on its reliability, or sense of shared purpose, as an EU member state.
While the intensity today is different, and the land war in Ukraine is certainly an exceptional state of affairs, competition and the pursuit of advantage in the international system are enduring and inevitable facts of life. We live in an era in which major revisionist powers are challenging and disrupting the status quo, emboldened by, and fully utilising, the potential offered by new technologies. In this context, challenges and disruptive activities invite countermeasures, which also have ramifications for the international environment, impacting on targets’ perceptions and future behaviour and so contributing to intelligence’s own version of the security dilemma. Hence, while UK intelligence highlights (and prosecutes) Russian human intelligence collection methods and warns against the threat posed by China, SIS publicises the possibilities presented by Silent Courier. This is the highly competitive, complex, and unstable international security environment that Blaise Metreweli faces as the new Chief of SIS.