The economic boom in the early decades of the new century brought prosperity to a third of humanity. But with the single-minded focus on economic growth, reinforced by the power of global markets, attention to social and environmental concerns declined. And the boom bypassed whole regions; even in rapidly growing countries, the surge in income and wealth was highly concentrated.

In many rural areas, income dropped and living conditions deteriorated. Much productive land in Latin America and in India remained locked up in large estates. Africa's burgeoning population faced acute shortages of farmland. Desperate for land, subsistence farmers pushed into marginal lands, cultivating hillsides and clearing forests. But marginal land eroded quickly and even good land degraded when poor farmers could not renew soils or grazed too many cattle on shrinking grasslands. Rural poverty increased and the flood of urban migrants swelled, creating vast urban shantytowns.

As disparities increased between the poor and those fortunate enough to live in industrial countries or in middle-class enclaves of the developing world, so did awareness of the vast gulf in lifestyles. Advertising and a booming travel industry brought new awareness and fueled growing resentment among the masses of people who desired the comforts and consumer products of the rich but could not hope to achieve them. Teenagers-now more than 1 billion worldwide and a volatile, mobile group--were especially susceptible to these influences, a growing army of the angry poor.

Rapid economic growth also brought rapidly worsening pollution to much of industrializing Asia and Latin America as sprawling factories spewed wastes into the environment. Ever larger numbers of cars and trucks choked urban streets, making the air hard to breathe. Deteriorating health conditions were increasingly evident-chronic lung disease in urban areas, an epidemic of cancer from polluted waterways, virulent new diseases emerging from devastated forests and estuaries. There were broader signs of environmental distress as well. One by one, the major marine fisheries collapsed, victims of overfishing by huge trawler fleets eager to supply international fish markets. Fish, produced almost entirely by aquaculture now, became a luxury food. Fishermen lost their jobs, but more devastating was the loss of the primary source of protein for three quarters of a billion people. Wood, too, became ever scarcer and more valuable as forest disappeared, and hundreds of millions of people lacked the firewood to cook their dinners. The reality of climate change was no longer debated-drought cycles were unquestionably more intense and more frequent, and severe flooding devasted large areas of farmland and low-lying coastal areas. Urban heat waves claimed thousands of lives.

As conditions became increasingly desperate, the voices of the disenfranchised got louder. A protest by fishermen in India became an army of more than 2 million poor people that converged on new Delhi, demanding redress of their dire economic straits. An unusually vicious killer smog in Mexico City left thousands dead and many more ill, igniting a protest in which people shut down the highways, bringing the city temporarily to a standstill. Syria and turkey fought a short but deadly war over the water of the Euphrates River. Attempts by landless farmers in Brazil to take over idle estates turned into bloody massacres at the hands of the landlord's hired armies. Protests by laid-off industrial and construction workers during an economic downturn in China turned into food riots and looting, with thousands of deaths; the conflict nearly brought down the government.

Contributing to the upsurge in violence, felt even in the industrial countries, was the growing power of organized crime on a global scale. Criminal organizations now controlled governments in several developing countries; elaborate computer crimes defrauded millions and toppled more than one major international bank. Armed clashes among competing criminal groups and repeated terrorist incidents created a growing sense of vulnerability. Public and private spending on security rose sharply, walled and guarded communities became a way of life, and many business executives employed bodyguards for themselves and their families. Few tourists visiting developing countries ventured beyond officially sanctioned sites and luxury retreats, all carefully guarded.

A flood tide of illegal migrants poured into rich countries, adding to the sense of being under siege. Immigrants were blamed for crime, for unemployment, for the spread of new diseases. The political demand to so something, anything about the problem became overwhelming. Europe repealed the Common Market's open border provisions, required high-tech identity cards, and instituted random street and highway checks; illegal foreigners were immediately deported. The United States, too, issued identity cards, removed due process provisions for non-citizens, and built an elaborate set of fences, concrete barriers, and electronic sensors along its southern borders. Racial and ethnic tensions escalated.

Africa's collapse, when it came, was not entirely a surprise. Despite attempts at reform, the continent's rapidly rising population, falling incomes, and corrupt governments proved overwhelming. Crime was often the only way to feed a family. As state after state foundered, leaving near anarchy, huge numbers of desperate refugees fled across borders, overwhelming the few stable countries. At the height of the troubles, more than 5 million people per year died of violence, hunger, and disease. Civil order collapsed in other regions, too, if more sporadically.

Faced with chronic instability in developing regions, the industrial world turned inward and the world economy stagnated. In their protected enclaves, their Fortress Worlds, the rich were like islands of prosperity in an ocean of poverty and despair. And yet even there, they could not entirely escape. The poor, bereft of all else, still found ways to export their misery in the form of crime, violence, and disease.