The World’s Detroits

The World’s Detroits

At the height of its wealth and power, Timbuktu was an important crossroads for trans-Saharan caravans laden with exotic spices and a storehouse of knowledge, boasting as many as 25,000 scholars and some 80 private libraries. In 1324, its ruler, Mansa Musa, brought so much gold on his pilgrimage to Mecca that it sparked hyperinflation in Cairo. By the time French explorers stumbled upon Timbuktu in 1828, it had become a dusty backwater, the forgotten capital of a long-forgotten empire. Today it’s not even one of the five largest cities in Mali, one of the poorest countries on Earth.

History is littered with the carcasses of once-great cities that couldn’t — or wouldn’t — adapt to changing circumstances. Political scientist Douglas Rae calls cities "among the least agile creatures … they move slowly, reactively, and awkwardly in response to change initiated by more athletic organizations." It has taken a century for the former trading hub of Istanbul to arrest the slow decline that began in 1498, when Portuguese explorer Vasco da Gama made a daring trip around the Cape of Good Hope in a bid to cut the Ottoman Empire out of the Asia trade. Detroit, in a death spiral with the collapse of its car business, might never succeed at such reinvention.

That’s why the top cities on this index all have one trait in common: They hedge their bets. Cities with a diverse mix of industries, like Chicago and Hong Kong, find it easier to retool when times change, while those that do only one thing well — Pittsburgh with steel, Glasgow with shipping, and Detroit with those cars — risk being casualties of globalization. Consider Chelyabinsk in Russia, an industrial powerhouse of the Soviet era that was dubbed "Tankograd" during World War II. Once home to some 2 million people, it’s now half that size. Ivanovo, another Russian city that was one of the world’s top producers of textiles, has shut down the extensive tram system it no longer needs.

Could today’s rising giants, like Wuxi, a rapidly growing Chinese city of 5 million, become tomorrow’s white elephants? Wuxi is home to Suntech, a leading manufacturer of solar panels. But Suntech has bet its future on old-fashioned silicon, while a more flexible rival technology, thin-film solar, gains market share. Some day, will we be calling Wuxi China’s Detroit?