Cyber defence in practice: A student reflection on a conversation with Brazil's cyber command chief

Structured as a conversation rather than a formal lecture, the event reflected the War Studies tradition of bridging theory and practice. It provided students with direct exposure to how cyber defence is conceptualised, organised and implemented within a military framework, while highlighting its wider implications for international relations, defence policy, and global cooperation.

One of the most compelling aspects of the talk was its focus on the everyday realities of cyber defence. Rather than presenting cyberspace as an abstract or purely technological domain, Lt Gen Soares de Sousa emphasised its organisational and human aspects. Cyber defence, he explained, is embedded within military security structures much like traditional defence domains, – yet its battlefield is largely imperceptible. This framing challenges common assumptions that cyber conflict exists outside military structures.

An illustrative detail that resonated with many attendees was the image of cyber defence personnel wearing military uniforms while working behind computer screens in office environments. This visual contrast encapsulated the hybrid nature of cyber defence: although it lacks physical combat, it remains firmly within the military logic of discipline, hierarchy, and national protection. Analytically, this reflects broader debates within security studies about the changing character of war – where operational environments may become less kinetic yet remain strategically consequential.

The discussion also highlighted how cyber defence capabilities are increasingly integrated into national infrastructure and large-scale events, such as preparations linked to COP30 in Brazil. In this context, cyber defence is not limited to countering military threats but extends to protecting critical infrastructure, communication systems and international diplomatic processes. In this sense, cyber defence reveals to be a form of preventive statecraft, reinforcing cyber defence as key instrument for threat containment in both domestic and international settings.

A recurring theme of the event was the recognition of cybersecurity as one of the major defence challenges of the 21^st century. Lt Gen Soares de Sousa underscored the growing role of artificial intelligence, noting that while Brazil has developed important cyber capabilities, it still operates within a global hierarchy where technological power is unevenly distributed. This acknowledgement highlighted that cyber defence is not solely about technological sophistication but also about strategic adaptation.

From an international relations standpoint, cyber defence emerged as an evolving practice shaped by competition and collaboration alike. The Lt Gen highlighted exchange programmes and professional interactions between military personnel from different countries, which allow states to learn from diverse approaches to cyber security and develop shared understandings of emerging threats. The emphasis on professional interaction between military personnel challenges traditional assumptions about sovereignty and deterrence: while states continue to pursue national advantage, the transnational nature of cyber threats encourages forms of dialogue and coordination that blur the boundaries between domestic defence and international security politics.

For students in the Department of War Studies, the event offered more than technical knowledge; it provided analytical depth and professional inspiration. From a student perspective, the talk demonstrated how concepts studied in International Relations and Security Studies materialise in real-world defence practices.

As an International Relations student, I found the event particularly valuable in illustrating how cyber defence blurs the boundaries between military strategy, diplomacy and global governance. Having previously taken a state intelligence module, the discussion resonated strongly with my academic interests, allowing me to connect theoretical debates on intelligence and security with real-world military practice. Learning directly from a senior military practitioner was especially valuable, since it added credibility and realism to debates often encountered only in academic texts. It was also particularly interesting to learn more about cyber security from a non-Anglo-American perspective. The discussion reinforced the idea that cyber defence is no longer a niche or auxiliary concern but a central pillar of contemporary security policy.

I also felt a strong sense of privilege associated with studying at King’s College London – an institution able to convene such high-level conversations and expose students to global defence perspectives. Events like this underscore the unique position of War Studies in fostering dialogue between scholars and practitioners, preparing students for careers that demand both analytical rigour and practical awareness.

Overall, the event offered a timely exploration of how states are adapting to security challenges in the digital age. Through the professional experience of Lt Gen Soares de Sousa, students gained a clearer understanding of cyber defence as both a military practice and evolving field within international relations. The discussion served as a reminder that the future of security will be shaped not only on land, sea, air and space – but increasingly, in cyberspace.