"Urbanization has already declared itself the mega-trend of the 21st century, with half the world’s population now living in cities for the first time in human history. While the implications for economic growth have been widely discussed, urbanization’s impact on diplomacy and sovereignty will be equally profound," say Michele Acuto and Parag Khanna.
On issues from climate change to security, cities are working together to solve the world's most profound challenges.
"As cities continue to arrogate major diplomatic and economic functions, should we still be talking about international relations?" ask the authors. "[T]hose living in the world’s principal cities anywhere often have more in common with each other than with their own compatriots."
"As sustainable urbanization comes to be seen as a unifying global priority, cities must be empowered rather than restrained to become more active problem-solving agents."