AS the influx of foreigners to America nears historic highs, Congress is mounting a new attempt to rewrite the nation's immigration laws that would significantly limit visas for legal entrants and tighten the borders for illegal ones.
Not since the turn of the century, with the arrival of millions of Europeans, has the issue of immigration generated such debate in the United States.
Critics say the surge, now mainly from Asia and Latin America, has had a disastrous economic effect: depressing wages, displacing workers, and crowding the nation's prisons and welfare rolls. Supporters of current policies argue that immigrants create more wealth than they consume.
As the US House opens debate this week on immigration reform, the idea that America must harbor the world's tired, poor, and tempest-tossed is clashing with the cold, pragmatic fact that immigration costs money.
"Of course we are a nation of immigrants, and our generosity toward immigrants will continue," writes Texas Rep. Lamar Smith, author of the House immigration-reform bill. "But our current immigration laws are broken and must be fixed."
Although the debate promises to be contentious in many respects, there is broad bipartisan support for many reforms, particularly on illegal immigration.
Here, Mr. Smith says, the signs of crisis are unmistakable. Forty percent of the babies born in California hospitals belong to illegal immigrants, he notes, and foreign-born convicts, mostly illegal immigrants, make up 29 percent of the nation's prison population.
According to the Bureau of Labor Statistics, 50 percent of the decline in real wages for low-skilled workers can be attributed to illegal immigrants, who are willing to work for less and thus drive down average wages.
To quell these trends, House and Senate bills would increase border patrols and inspections, crack down on abuse of tourist visas, stiffen penalties for alien smuggling, speed deportations, redouble enforcement of labor laws, and make illegal immigrants ineligible for most federal, state, and local benefits.
The bills would also create a telephone hotline employers would have to call to check the immigration status of new hires. Civil libertarians call the measure Orwellian, and business groups denounce it as another federal mandate. Smith has indicated he might make the system voluntary.
But beyond this glitch, few in Congress expect the illegal immigration bills to run into serious trouble. The real action will be on the other side of the coin: legal immigration.
Each year for the last 10 years, the US government has admitted about 1 million legal immigrants. Some are refugees seeking political asylum. Others are skilled workers sponsored by businesses, and the bulk are relatives of prior immigrants.
Politically, the issue is sensitive for Republicans. On one side, presidential candidate Pat Buchanan has advocated a five-year moratorium on legal immigration, and Wyoming Sen. Alan Simpson, sponsor of the Senate bill, backs a one-third reduction.
But pro-business Republicans oppose limits. In particular, they question a provision that would reduce the number of skilled workers admitted each year from 140,000 to 90,000, and another that would levy a $10,000 tax on each foreign worker hired.
Chief among the critics of these proposals are executives of high-technology companies that rely on foreign engineers and computer programmers. To maintain the nation's competitive advantage and keep firms in the US, they say, it's necessary to leave the gates open for the world's best and brightest.
Critics counter that the real motive of the businesses is a preference for cheap foreign workers.
In the face of pressure from businesses, Mr. Simpson withdrew these measures from consideration. But he may reintroduce them when the legislation comes to the floor.
Yet the larger economic problem created by legal immigration, Smith says, is the number of legal immigrants admitted each year under family preference programs. Often, he says, these immigrants have no marketable skills and wind up on welfare.
According to George Borjas, a public policy professor at Harvard University, 21 percent of immigrant households receive some form of public assistance, as opposed to 14 percent of other households. Some studies have found that immigrants receive $25 billion more in benefits than they contribute in taxes.
To correct this problem, House and Senate bills would overhaul family-based immigration programs, cutting admissions from 465,000 to 330,000 annually and giving first priority to spouses and minor children.
In addition, the bills would restrict the ability of legal immigrants to receive benefits, make it easier to turn away foreigners seeking asylum, and cut back temporary work visas.
Yet many liberal Democrats, particularly those from high-immigrant areas, argue the proposals are unnecessary.
"I know of no economist worth his weight in salt who says that immigrants on the whole are negative economically," says California Rep. Xavier Becerra (D). By starting businesses, creating jobs, and paying taxes, he says, immigrants enliven the economy.
Last week, opponents of legal immigration bills won an early victory when a Senate committee voted to consider legal and illegal immigration proposals separately, effectively lowering the chances that the less-popular legal immigration reforms will survive.