"What does the global telecommunications company Huawei, a hacking-for-hire outfit in India, and Russian cyber criminals have in common? They all share a special relationship to the state, which significantly shapes the politics of cyber(in-)security. The relationships between these actors and states are complex and constantly evolving, yet not well understood. Semi-State Actors in Cybersecurity provides an insightful theoretical and empirical analysis of the political challenges raised through the interaction between such semi-state actors and states. The book uses a historical analogy to pirates, privateers, and mercantile companies to uncover the political constitution and interaction of cybercrime, state-sponsored hackers, and large technology companies. Drawing on historical archival sources and innovative theory, it identifies the parallels between today's cyber(in-)security and the historical quest for gold and glory on the high seas during the 16th - 19th centuries. The book explains what the co-presence of semi-state actors means for national and international security and shows that the proximity to the state in these relationships is a key determinant of cyber(in-)security. Through so doing, it clarifies how semi-state actors were historically and contemporarily linked to understandings of statehood, sovereignty, and the legitimacy of the state. Semi-State Actors in Cybersecurity offers insights with regard to the political use of state proximity by attackers and defenders, state collaboration with cyber criminals, and the cooperative and conflictive relations of large technology companies to the state. This offers a fresh perspective for understanding the international politics of cyber(in-)security"--