Nearly two-thirds of the world's population will live in cities by 2030, with most people middle class, connected by technology, protected by advanced health care and the United States and China perhaps cooperating to lead the way.
That's the best-case scenario in a report, Global Trends 2030, released Monday by the U.S. government's National Intelligence Council.
In the worst-case scenario, the rising population leads to conflict over water and food, especially in the Mideast and Africa, and the instability contributes to global economic collapse.
The study is the intelligence community's analysis of where current trends will take the world in the next 15 to 20 years, intended to help policymakers plan for the best and worst possible futures.
One bright spot for the U.S. is energy independence. "With shale gas, the U.S. will have sufficient natural gas to meet domestic needs and generate potential global exports for decades to come," the report said.
Among the major trends: the rise of a global middle class that is better educated, connected via technology and healthier due to advances in medicine. Power will no longer reside with one or two key nations but be spread across networks and coalitions of countries.
In countries with declining birth rates and an aging population like the U.S., economic growth may slow. Sixty percent of the world's population will live in cities.
Food, water and energy will be more scarce. "Nearly half of the world's population will live in areas experiencing severe water stress," the report said. Africa and the Middle East will be most at risk of food and water shortages, with China and India also vulnerable.
Among the anticipated crises is the worry of global economic collapse, fighting among nations that don't adapt rapidly enough and the possible spillover of instability in the Mideast and South Asia to the rest of the world.
Technology is seen as a potential savior to head off some of this conflict, boosting economic productivity to keep pockets filled despite rising population, rapid growth of cities and climate change.
The report outlines several "Potential Worlds" for 2030.
Under the heading "Stalled Engines", otherwise known as the "most plausible worst-case scenario, the risks of interstate conflict increase," the report said. "The U.S. draws inward and globalization stalls."
In the most plausible best-case outcome, called "Fusion," the report said, "China and the U.S. collaborate on a range of issues, leading to broader global cooperation."
The report warns of the mostly catastrophic effect of possible "Black Swans," extraordinary events that can change the course of history. These include a severe pandemic that could kill millions in a matter of months and more rapid climate change that could make it hard to feed the world's population.
Two positive events are also listed, including "a democratic China or a reformed Iran," which could bring more global stability.