The cliché that the United States is a nation of immigrants is becoming even more true. The latest estimate from the Labor Department shows that almost half of the 8.8 million people who joined the U.S. labor force over the past six years were foreign-born.

If any one statistic stands as proof that the federal government has to address concerns over its immigration policies, that would be it. But the reason may be counterintuitive. The fact is, without that surge of immigrant workers — many of whom came here legally and many of whom did not — the economy could not have shrugged off the recession of 2001 and expanded as rapidly as it has. The country needs workers, and we don’t seem to be supplying a sufficient number from the native population. So many more will have to come from other countries, or companies will have to flee overseas because the labor market here has dried up.

At the same time, absent a coherent, workable and widely accepted policy for allowing foreign-born workers access to U.S. jobs, tensions will continue to rise. Yet there are those who favor much stricter immigration controls and who would like to exploit those tensions and capitalize on racial and ethnic fears of competition for scarce employment opportunities to drive the debate their way.

Broadly speaking, however, now appears to be a good time to address the two principal sticking points of overhauling immigration law: the demands of employers for temporary workers, and the shadowy status of the 12 million or so who are living and often working here illegally.

That’s because the U.S. job market is generally a friendlier place for all workers these days than it has been for years. The result may be an ebbing of the political pressures that are an outgrowth of globalization and the other unsettling economic forces of our time.

Consider the facts: The labor force grew in 2006 at the fastest pace in six years. At the end of the year, 63.4 percent of the population was employed, the most since the economy was in recession six years ago. The jobless rate fell in March to 4.4 percent, matching the five-year low set in October. Wages also are rising for rank-and-file production workers. After adjusting for inflation, average weekly earnings have shown year-over-year increases for 10 straight months, and for 13 of the past 14. Those gains have more than reversed the effects of three straight years of declines, and real earnings in March were higher than they have been at any time since early 1980.

Of course, those figures are aggregates, and they hide differences based on age, sex, and race or ethnicity. And such differences can be politically, socially and economically problematic.

In particular, the picture isn’t very rosy for African-Americans, who are less likely to join the labor force than are whites, Asians or Hispanics. Moreover, though job statistics for blacks have improved along with those for the population at large, adult black men continue to have an especially hard time finding work and are more likely to be unemployed than virtually all groups, except teenagers.

This less-than-happy state of African-American employment is a potential fissure that opponents of guest workers and a path to citizenship for those currently here illegally would like to widen.

An advertisement by the Coalition for the Future American Worker contends that immigration continues to be a disaster for black Americans. The group makes much of a study that purports to link a decline in black employment and wages — and notably a rise in the percentage of blacks in prison — to a surge in low-skilled immigrants, legal and otherwise, between 1960 and 2000. The provocative study was published in September by three academics, including Harvard professor George J. Borjas, a prolific author of papers that seek to show the downsides of immigration.

It’s not clear, however, that this line of attack will be successful.

First, public opinion surveys, including one by the Pew Research Center a year ago, show that black Americans are generally more accepting of immigrants than are whites and more sympathetic to their problems. Blacks do tend to say more often than do whites that they know someone who lost a job to an immigrant, but this doesn’t appear to translate into a significant objection to the presence of foreign-born workers.

Second, black lawmakers in Washington have so far tended to support the sort of immigration overhaul proposed by President Bush and favored by most Democrats. Third, there is a shelf full of academic research that runs counter to that done by Borjas and that shows little or no connection between immigration and lost job opportunities or lower wages.

Finally, even the authors of the Borjas study recognize its controversial nature and note that immigration has not been the sole — or even the primary — cause of black labor troubles in the latter part of the 20th century. Crack cocaine trafficking created a crisis in inner cities, to cite just one other cause.

Legitimate immigration concerns already divide the public — and both political parties — and will require careful deliberation to resolve. Resorting to what amounts to racial politics seems an excessive escalation of a debate into ugly territory.