I’m embarrassed to admit that I only recently got around to reading Lant Pritchett‘s Let Their People Come: Breaking the Gridlock on Global Labor Mobility.  The full text is free and packed with goodness, but I learned the most from Pritchett’s chapter on “ghost” versus “zombie” economies.  Key idea:

Large and persistent
declines in labor demand in a region, perhaps because of technical
changes in agriculture or changes in resources, create two possibilities, which
I call “ghosts” or “zombies.” If labor is geographically mobile and hence labor
supply is elastic, then large declines in labor demand will lead to large outward
migration–the process that created “ghost towns” in the United States.
However, if labor demand falls in a region and labor is trapped in that region,
by national boundaries for instance, the labor supply is inelastic and all the
accommodation has to come out of falling wages. A region that cannot
become a ghost (losing population) becomes a zombie economy–the economy
might be dead, but people are forced to live there.



Is this a big deal in the real world?  Yes!

There are three sources of evidence, which together suggest that there are typically large shifts in the desired populations of regions. Though it is extremely difficult to separate out which of these are shifts in just an “unconstrained desired” population (due to remediable factors like policies, or, optimistically, institutions) and which are shifts in “optimal” populations, there is some evidence from comparing regions of countries (which share many policies and institutions) that some large fraction of the shifts in desired populations are also shifts in optimal population. These shifts in desired population are accommodated differently depending on the conditions for labor mobility. The three empirical examples are (1) regions of the United States, (2) comparisons of within-country versus cross-country variability of population and output per person growth rates, and (3) population versus  output variability in history.

Peek at evidence on (1):

I have assembled five regions of the United States, which, since I created
them, I will name: Texaklahoma (Northwest Texas and Oklahoma), Heartland
(parts of Iowa, Missouri, Kansas, and Nebraska), Deep South (parts of
Arkansas, Mississippi, and Alabama), Pennsylvania Coal and Great Plains
North (parts of Kansas and South Dakota). Even with the constraint of contiguity
and (mostly) convexity, one can assemble large territories that have seen
substantial absolute population decline. The Great Plains North is a territory
larger than the United Kingdom, and its population declined 28 percent from
1930 to 1990. Its current population is only a bit more than a third the population
it would have been if its population growth had been at the rate of natural
increase. The Texaklahoma region is bigger than Bangladesh and is now
only 31 percent the population size it would have been in the absence of outmigration.

Peek at evidence on (2):


Peek at evidence on (3):

The nineteenth century was truly an “age of mass migration” (Hatton and
Williamson 1998), because many of the “areas of recent settlement” had open
borders with respect to immigrants (at least with certain ethnic and national
origins). It was also an era of rapid reductions in transport costs and shifts
toward freer trade in goods, open capital markets, and massive movements in
capital–the first era of globalization. Hence, this period is an interesting
example of the question: “How would we expect geographically specific
shocks to be accommodated in a globalizing world?” Comparing Ireland to
Bolivia highlights the obvious: that nearly all developing countries with negative
shocks have seen their populations continue to expand rapidly, while
when there was freer labor mobility in the international system, labor movements
accommodated negative shocks

Bottom line: If you can believe that huge areas within many countries are optimally empty (or nearly empty), the same could be true for entire countries.  Ghost countries, like ghost towns, won’t look pretty.  But this is a classic case of “Is a place still ugly if nobody sees it?”  Immigration restrictions turn ugliness few people ever see into ugliness millions experience every day.