Andrew Denning is Associate Professor of History at the University of Kansas, USA. His research focuses on histories of mobility, technology, the environment, and empire in the twentieth century and his publications have appeared in American Historical Review, The Atlantic, and Journal of Modern History.Heidi J.S. Tworek is Canada Research Chair and Associate Professor at the University of British Columbia, Canada. She has published over 40 journal articles and book chapters on communications, health, international organizations, and business history plus the award-winning News from Germany (2019). She co-edits Journal of Global History.