It is hard to know with certainty where and why cities will falter and fail in the 21st century. It is even more difficult to predict which cities are going to thrive and survive. What is more certain is that unprecedented urbanization will play a defining role in their success or failure. To put it in crude terms: the fight for future security and development will be won or lost in the metropole.
The direction of city growth is pointing south and east. Most population growth in the coming decades will occur not in urban centers of North America and Western Europe, but in the sprawling cities and slums of Africa and Asia. Just three countries — China, India and Nigeria — will account for 40 percent of global growth over the next decade. People are not just moving to cities: cities are coming to them.
The speed and scale of the urban revolution is mesmerizing. Just 3 percent of the world’s population lived in cities in the early 1800s as compared to over 50 percent today. There are currently over 4,000 cities with more than 100,000 inhabitants around the world, home to over 4 billion people. Just 600 of them account for more than two thirds of global gross domestic product. Among the latter are 34 megacities, home to one-fifth of humanity.