But the slowed migration has significant political effect.

WSJ: Recession Slows Migration in U.S.

The numbers of African-Americans returning to the South are not as large as those seen during the Great Migration, but the trend has resonance because of the place the region occupies in black history and mythology.

CNN: Family roots lure many African-Americans back to South

The recession may have slowed the pace of net migration, but the essential pattern has remained in place.

FORBES: New Geographer

The weak recovery has slowed migration, but expensive, overregulated and dense metropolitan areas continue to lose population to lower-cost, less regulated and generally less dense regions.

FORBES: Where Americans Are Moving

Second, Fogel is right to note that migration of labor to cities has been the engine of Chinese growth, but that process has stalled in the global economic downturn.

FORBES: New Asia

But the mass migration of newcomers, who have increased tremendously as a portion of the population, has also sparked widespread resentment among Singaporeans faced with ever greater congestion, crowding, high property prices and ever-greater competition for good jobs.

FORBES: Decline Of The Asian Family: Drop In Marriages, Births, Threatens Economic Ascendancy