Recent violence in Northern Virginia has some officials going like gangbusters.

Rep. Frank R. Wolf (R-Va.) and state Attorney General Jerry Kilgore (R) each has created a task force to crack down on gang activity. Wolf now is pressing Congress for $10 million for a national gang-intelligence center.

Gov. Mark R. Warner (D) has set up a "strike force" to target gangs in Virginia. The Fairfax County Board of Supervisors also has established a gang-prevention council. And that county's new police chief says thwarting gang recruitment is one of his principal goals.

Although gang warfare in Northern Virginia has been festering for years, the community was galvanized in May when a teenager's hands were cut off by a rival gang member. The alleged attacker, 18-year-old Hayner R. Flores, reportedly belongs to the Mara Salvatrucha-13 gang, which has about 3,500 members in this area. Like many of his fellow gang members, Flores is in this country illegally.

Because most gang members are never arrested, it is impossible to know the status of all of them, but Arlington police estimate that illegal aliens make up half of the gang membership in that jurisdiction. (Fairfax and Alexandria police say they do not keep such figures.) Because police are leery about being accused of "profiling," the number may be much higher.

Indeed, Dan Stein, executive director of the Federation for American Immigration Reform (FAIR) estimates it at 70 percent to 80 percent. The Virginia attorney general's office agrees that the percentage is "significant."

Does that surprise anyone?

People residing here illegally obviously aren't the law-abiding type. Certainly, all illegal immigrants are not murderous thugs, but, by definition, they are criminals. Merely enforcing laws already on the books would eviscerate the gang population.

It is impolitic to acknowledge that not all immigrants are sympathetic strivers, but the reality is that Americans don't benefit from all those who would come here. FAIR cites studies estimating that 400 million people would emigrate to the United States tomorrow, if they could get in. Nearly 4 million are waiting for visas; some have waited as long as 17 years. Individuals so intent on playing by the rules would be assets to our society. It is they -- not unassimilated outlaws -- who warrant our sympathy and welcome.

The population of Fairfax County now is 25 percent foreign-born, and that statistic is not without consequence. As the immigrant population exploded during the 1990s, the county's poverty rate rose by 54 percent. Property values decline when immigrants pile into overcrowded houses. Schools are burdened by children who cannot speak English. Virginia taxpayers spend millions each year on welfare, rent subsidies, jail cells and medical care for illegal aliens.

Fortunately, not everyone suspends reason regarding immigration. Sen. George Allen (R-Va.) recently secured federal funds to help Virginia localities defray the cost of jailing illegal aliens who commit other crimes. Rep. Eric I. Cantor (R-Va.) introduced a bill that would have made legal presence in the United States a prerequisite to getting a driver's license.

Virginia's General Assembly also made laudable efforts this year. Lawmakers tried to prevent state colleges from admitting students who are in this country illegally. They gave police authority to detain illegal immigrants who have returned to this country after being convicted of a felony and deported.

But supporters of the law battle powerful panders. Warner not only doesn't want to penalize criminal residents, he wants Virginia taxpayers to provide them with a college education. President Bush wants Americans to pay non-Americans Social Security benefits. And some Northern Virginia officials balk at enforcing immigration laws.

But how can we counter gang warfare without targeting a principal cause of the problem? As long as criminals have friends in high places, they will continue to plague our communities.