The "Minutemen" have left their posts along a short stretch of the Arizona border with Mexico after their month-long effort to stem the flow of illegal immigration. The Minuteman Project, which ended May 1, never drew the thousands of volunteers organizers predicted would show up along the 23-mile stretch of desert in Cochise County, Ariz., which has been a favorite crossing point for thousands of illegal aliens. At month's end, fewer than 900 men and women had joined the ragtag group that some hailed as "citizen volunteers" and others condemned as vigilantes, and only 335 illegal aliens were apprehended as the result of their efforts.

 That's about half the number of illegal aliens the U.S. Border Patrol usually picks up each month along that same stretch of border -- which the Minutemen say is proof of their effectiveness. But the Border Patrol has a different explanation. The drop in border crossings is "not attributed to any civilians on the border at all," agent Andrea Zortman told National Public Radio recently. In March 2004, she explained, "we began the Arizona Border Control Initiative Phase I, and with that, we brought in additional agents, additional vehicles, assets, infrastructure, technology and whatnot." The Mexican government, too, stepped up its efforts to patrol the border, sending in troops to scare off Mexicans hoping to sneak into the United States near where the Minutemen set up camp with their lawn chairs and binoculars.

 Of course no one knows if some of these illegal aliens simply hiked a few extra miles to avoid the new agents and Minutemen and crossed elsewhere. But the Christian Science Monitor reported recently that to extend the same level of manpower along the entire 1,400-mile border with Mexico would require "60,000 people -- and probably a permanent presence, experts note." There's a much better way to deal with the problem, but unfortunately, most politicians seem terrified even to discuss it.

 The problem of illegal immigration could be vastly improved, if not solved, if we'd reform legal immigration.  The dirty little secret is that we need more immigrants than we currently allow into the U.S. legally, whether we are willing to acknowledge it or not. Now, I know public opinion polls show that most Americans don't want more immigrants. Only 9 percent of Americans favor increasing immigration, according to one recent poll by Republican pollster Ed Goeas. But the vast majority of adult illegal aliens are gainfully employed -- and not at below-minimum wage jobs either -- which means that the American labor market easily absorbs them, and, in fact, has become dependent on them.

 Although some immigration opponents claim that immigrants take jobs from Americans, there is little evidence to support this. One study by Rob Paral of the Immigration Policy Center shows that employment in one-third of all job categories would have contracted during the 1990s in the absence of newly arrived immigrant workers, even if all U.S.-born workers with recent experience in those categories had been re-hired.  According to Paral's analysis, "data from the 2000 census indicate that even if native workers could readily have moved to any part of the country in which jobs were available during the 1990s, and even if they had been willing to accept any job offered, there would not have been nearly enough unemployed native-born workers to fill all available jobs."

 Without the more than 12 million immigrants who arrived in the 1990s -- including some 5 million illegal aliens -- the U.S. would have created fewer jobs, experienced slower economic growth and maintained a lower standard of living for everyone. Large segments of agriculture, the poultry and beef industry, certain manufacturers, and other employers faced with labor shortages or skyrocketing wages would have been forced out of business or moved their production abroad.

 Even if it were possible to put native-born workers into all jobs now performed by immigrants, would it make sense? We spend billions of dollars each year to educate Americans. Do we really want Americans with 13 or more years of education picking lettuce, processing chickens or cleaning toilets -- and are we willing to pay them $18 or $20 an hour to do so? Doesn't it make more sense to match relatively low-skilled, foreign-born workers to jobs that require few skills?

 If we changed our immigration laws to allow needed workers to immigrate legally, we'd largely solve our illegal alien problem; the Minutemen could go home permanently; and the Border Patrol could devote itself to keeping out drug dealers and terrorists. Too bad politicians aren't even willing to consider this option.