Blue-collar workers who voted for Barack Obama may want to reconsider their support in light of current unemployment trends. The president is reopening a campaign for "comprehensive immigration reform" (some call it amnesty) even as jobless rates keep rising.

Legal and illegal immigrants have swelled America's labor force in the recent years. In fiscal 2008, 1.45 million new migrants were granted work permits. Combined with the influx of millions of undocumented workers, this excess supply became the equivalent of the housing bubble — it was bound to burst.

Since 2007, jobless rates have doubled. In the first quarter of this year, immigrant unemployment stood at 9.7 percent, the highest level since 1994, when data began to be collected on migrants. Overall unemployment topped 8.6 percent, also the highest in 15 years.

The blue-collar sector has been hit especially hard. Some 31 million native-born and immigrant workers with a high-school degree or less are now jobless. Unemployment in this category is now a record 14.7 percent for immigrants and 19.5 percent for natives.

Not surprisingly, northbound movement across America's southern border has slowed. Without prospects of a job, there's less incentive to come.

But if the Obama administration and congressional Democrats enact yet another "regularization" of undocumented workers, the U.S. workforce will artificially inflate — further depressing wages. A continued surfeit of workers is red meat for the U.S. Chamber of Commerce, so the Obama administration can count on bipartisan aid from the likes of Sen. John McCain, R-Ariz., and other "business Republicans."

A better course would be strictly enforcing existing immigration laws.

"If the United States chose to more vigorously enforce immigration laws over the next year and this resulted in one or two million illegal workers deciding to leave, it could significantly improve the employment prospects of our poorest and least educated workers," said Steven Camarota and Karen Jensenius of the Washington-based Center for Immigration Reform.

That's a plan that might actually work for workers.

— Scripps Howard News Service