Stephen Mercado, who earned a master’s degree in international affairs at Columbia University’s School of International and Public Affairs, is a retired officer of the CIA’s Open Source Enterprise (originally the Foreign Broadcast Information Service). A researcher primarily interested in Japanese intelligence history and Asian open-source intelligence, he is the author of Japanese Spy Gear and Special Weapons: How Noborito Scientists and Technicians Served in the Second World War and the Cold War (Pen & Sword Military, 2025), The Shadow Warriors of Nakano: A History of the Imperial Japanese Army’s Elite Intelligence School (Brassey’s, 2002), a dozen articles, and several dozen book reviews.