This book revolves around a central puzzle. In an age when technology connects our societies more than ever before, how can hatred and violence also be on the rise? Whether witnessing distant atrocities by Islamic State insurgents, or a neo-Nazi parade through the local town square, we find ourselves asking: How can we be more connected, yet also more divided?
The answer offered by this book is that the emergence of violent divisions between human groups is systematically influenced by the patterns of communication generated by different communication technologies. I argue that patterns of communication are central, because the generation of collective violence requires the production and dissemination of ideas justifying collective violence. Consequently, the introduction of different forms of communication technologies into human societies has also generated systematic shifts in their patterns of political conflict. In short, while increased connections that span across existing differences are likely to foster political moderation and unity, increased connections that flow along segregated lines are likely to foster polarization and violent extremism.
The project breaks new ground, by offering the first global-scale, macro-historical quantitative evidence for the central role of mass communication technologies in the construction of violence and peace in human societies. Spanning the past two centuries of the development of modern states, from the early introduction of mass literacy and newspapers in the 19th century, to the rise of cell phones and the internet in the 21st century, the book demonstrates that the presence of mass communication technologies that reach across existing social divisions has been central in determining which societies consolidated into stable nation-states, and which societies spiraled into polarized divisions and armed insurgencies. The evidence also shows that there are reasons to be concerned about recent developments, as the increasing dominance of technologies that reinforce existing lines of segregation, such as cell phones and the internet, are instead making it easier for divisive and violent ideas to achieve success.