Who can quarrel with Mark Krikorian's argument that the Home Front has new meaning today — that protecting our children, and our way of life, now poses challenges we hardly imagined a few years ago. Still, I've read his piece over and over, and I don't see a workable strategy there.

He's full of bluster and menacing talk — to the point, rather tastelessly in my view, of threatening the president. But what exactly would he do to protect us? Talk is cheap — and so is scare-mongering.

Consider his implied solutions. Not one of them is practical, and none would make us safer.

Sealing the borders? Would that mean barring the 30 million tourists and businesspeople who come each year? The millions who commute across the border on a daily basis? Even if it meant only those who come to settle — some million a year — who then would man our farms? (About 80 percent of U.S. farm hands are foreign-born.) Who would do the dirty jobs in hotels and restaurants? Where would we get nurses? (By 2020, we may be a million short — a gap we can't fill without foreigners.) And our labor needs, skilled and unskilled, will only grow as the economy reheats. According to the Labor Department, between now and 2010, we'll create eight million new jobs for unskilled workers. How many native-born Americans are going to want to fill those unpleasant, low-paying slots?

Then there's the idea of deporting the illegal workers already here. Quite apart from what that would do to cripple several industries and devastate regions areas where immigrant-dependent businesses are the major employers, just how would we go about rounding up and shipping out some seven million foreigners? Even in the face of the terrorist threat, most Americans would have trouble stomaching that.

Nor would reducing legal immigration help us cut the number of illegal entries. On the contrary — it would only increase the share of needed workers who would be forced to come illicitly. The economic currents swirling in the world today can't be regulated from Washington. The flow of laborers can't be turned on and off. And if we try to do so by lowering ceilings, we will only force more of the flow underground — and as a consequence, make ourselves less safe.

Think for a minute about the Mexican busboy who so frightens Mark Krikorian. The truth is that busboy is going to come anyway. But he poses a threat only if he's forced to sneak in — and the more like him who end up sneaking in, the harder it is to isolate and stop a bona fide terrorist. So doesn't it make more sense to admit the Mexican legally, ensuring that he's who he says he is and has proper papers, eliminating the livelihood of the smugglers and forgers who exist to help him, but moonlight by assisting terrorists?

None of this means we can't secure our borders. We can and must. We need better intelligence, more effective screening, increased information sharing among agencies, better technology at entry points, more cooperation with neighboring countries. But the most important thing we can do — the only way we can hope to regain control of our frontiers — is to set an immigration ceiling realistic enough to be enforceable.

Instead of trying to do the undoable, why don't we set ourselves a challenge we can meet? An America as successful as we are overseas, both militarily and in the gathering of intelligence, can surely win the war on the Home Front, too — but only if we recognize who the enemy truly is and plan our strategy accordingly.

— Tamar Jacoby is a senior fellow at the Manhattan Institute and author of Someone Else's House: America's Unfinished Struggle for Integration.

Tamar is telling us that because most illegals are just hard-working folk doing our dirty work for us, "there's rarely any mistaking them for the kind of monsters who sneak into the country to kill Americans." Perhaps she can offer her services to Tom Ridge; since she seems to know who the terrorists are, she might identify them for the authorities.

Of course, neither Tamar nor anyone else knows who the terrorists are. Dozens of hardworking, family-oriented people from overseas have already tried to kill us, and there's every expectation that more will try.

More ludicrous, though, is the contention that immigration is somehow fixed at one million per year, but that "our ceilings accommodate only about three-quarters of that flow." Immigration creates more immigration, and the development of industries where immigrants are concentrated is distorted by the huge and continuous supply of cheap foreign labor. In California, for instance, the acreage planted in labor-intensive fruits and vegetables has been steadily increasing, precisely because farmers are basing their planning on the expectation that the illegal flows won't be cut off. If the inflow of illegal workers were reduced, and the outflow were increased, farmers would start making different choices-i.e., planting carrots instead of strawberries, since the harvest of carrots is mechanized.

Mass immigration actually slows the process of technological development in industries that have become addicted to it. Whether it's agriculture, garment manufacturing, construction, or even services, the incentive to produce more output with fewer workers is diluted because of the loose labor market created by immigration. As the late Julian Simon said: "It is important to recognize that discoveries of improved methods and of substitute products are not just luck. They happen in response to 'scarcity' — an increase in cost. Even after a discovery is made, there is a good chance that it will not be put into operation until there is need for it due to rising cost. This point is important: Scarcity and technological advance are not two unrelated competitors in a race; rather, each influences the other."

The opponents of immigration-law enforcement posit a false choice: between the mass deportation of all eight million illegal aliens tomorrow, or amnesty ("Earning legal status," in Tamar's delicate phrasing). Instead, the realistic approach to this issue — one which acknowledges not only the huge numbers involved but also the addiction of certain sectors of the economy — is to start enforcing the law and reduce the illegal population through attrition — and attrition will gradually increase the cost of labor in some sectors, and thus spur needed innovation.

Each year, some 400,000 people leave the illegal population, some by getting green cards, others by leaving the country voluntarily, yet others through deportation. The problem is that they are more than replaced by the 700,000 new illegal aliens who settle here each year. The solution is obvious: Reduce the number of new illegals coming in and increase the number leaving, so that instead of increasing each year, the illegal population will start falling. For starters, we do this by punishing the knowing employment of illegals (Tyson Foods, now on trial in Chattanooga for alien smuggling, will think long and hard before hiring illegals again); by denying illegals access to bank accounts, drivers licenses, mortgages, higher education, etc.; by tracking down and deporting foreign visitors who overstay visas; and by prosecuting and imprisoning those who repeatedly sneak across the border.

I could go on, but a listing of possible tactics for controlling immigration isn't the point; it's the will to control immigration that's lacking, even at this late date. It seems that the lives of thousands more of our countrymen will have to be sacrificed at the altar of libertarian utopianism before we will muster the will to act.

— Mark Krikorian is executive director of the Center for Immigration Studies.