One of the by-products of the Ukraine war has been the emergence of the online “Z-Universe," an enormous network of websites and social media accounts named after a popular pro-war symbol. It is most active on Telegram, which, unlike Twitter and Facebook, is not banned in Russia. All its participants spread pro-Kremlin and anti-Ukrainian propaganda, publishing information that may or may not be true, but which legitimizes the war and the killing of Ukrainians. The Z-Universe seems chaotic, but it is actually very complex — and hierarchical. At the top are politicians and Kremlin officials, such as former Russian President...