FRONT PAGE: "The Great U-Turn: Global Migration Flows Reverse for the First Time Since the Depression as Work in the Rich World Dries Up," by Patrick Barta and Joel Millman, Wall Street Journal, 6-7 June 2009.

This is a huge and important shift, one that will last so long as the West remains mired in slow growth, which could be for years. As economists note, "the result is potentially the biggest turnaround in migration flows since the Great Depression."

Those readers who go back all the way with me to the New Map remember that one of my key four flows was "people" from the Gap to the Core. While I can't see this slowdown lasting forever, because the Core will continue to age and thus depopulate (without replenishment by immigration) and roughly 4/5ths of global population growth over the next four decades will be concentrated inside the Gap, the economic and thus political stress that this reversal of flow will put on many weak states inside the Gap may be very bad.

Already we've seen the slowdown and then drop in remittances, the key financial flow resulting from all those migrant workers laboring outside their countries of origin.

Many analysts naturally question "whether the latest migration reversal will outlast the current recession." Again, much depends on the recovery in the West, plus the alternative for some workers simply to find better prospects back home in their own emerging markets. This has already happened with lotsa Chinese and Indians. Skilled workers are now expected to return to those countries from the West at a rate 8 times higher than in the past. There should be no good reason for their return, no matter when Western economies recover.

As far as the U.S. is concerned, according to Pew Hispanic Center demographer Jeffery Passel, "What we're seeing is the normal outflow" and "a huge drop-off in the inflow" from the south.

No great mystery there. Your average Mexican says to himself: Would I rather sit out the downturn in America, where things are getting decidedly less friendly? Or back home where things will be cheaper?

That's an easy choice.

Something to keep an eye on as the recovery progresses.