Americans are divided over many issues relating to illegal immigration. But almost everyone agrees that illegal aliens who commit violent crimes should be deported.

Recent violent gang activity shows that disregard for our laws doesn't end after an immigrant enters the United States illegally. Some become involved in street gangs, such as the notorious MS-13 (which has international ties), and commit some of the group's most heinous violent crimes.

In the last two years, the United States Immigration and Customs Enforcement (ICE) agency has significantly increased its efforts to find and deport illegal-alien gang members who commit crimes. Through this ramped-up effort, the agency is working to enforce immigration laws against the worst offenders -- and it hasn't received the credit it deserves.

Instead of trying to federalize more and more state crimes, Congress should expand existing federal programs that address a true national responsibility. ICE's recent initiative is actually a more effective use of federal resources in fighting gang crime.

Most crime committed by gang members is better addressed by local authorities, but ICE's recent initiative demonstrates that there are important areas in which the federal government can act to ease the burden on state and local resources, while continuing to satisfy federal priorities. Simply enforcing our immigration laws is a big step.

In 2005, ICE stepped up its effort to target illegal aliens involved in gangs through a program called Operation Community Shield. Agency officials work with state and local authorities to arrest, prosecute and seek the removal of illegal alien gang members.

ICE helps fill gaps on intelligence. Among other things, local law enforcement shares information from its gang database with ICE agents, who use it to search through their larger immigration database. If gang members are either here illegally or eligible for removal based on their criminal convictions, ICE can deport them. The agency says its initiative has led to a 533 percent increase in gang member arrests since its inception and a 134 percent increase in arrests from 2005 to 2006. That's 7,655 individuals, from more than 700 gangs, arrested on immigration and criminal violations since 2005.

The increase in the number of arrests is encouraging, even though this is only a small percentage of the total number of criminal, illegal aliens living in the United States.

In 2005 (the last year for which numbers are available), ICE deported 89,406 aliens. However, a targeted approach that aims at the worst offenders, such as violent gang members, may reduce crime more than the numbers suggest. Often a core group of repeat offenders are responsible for most of the criminal activity in a given area. This is especially true of gang crime, where organized activity adds significantly to the rate of crime.

Federal officials who want to fight criminal street gangs should take note of Operation Community Shield. This initiative shows how criminal activity can be fought effectively without violating our federalist structure of government. Just as it's the role of the states to use police power to protect citizens from crime, it's the role of the federal government to protect our country through the enforcement of our immigration laws. It's essential to our homeland security, and it should be a priority.

Unfortunately, many members of Congress seem to think the solution is more federal criminal law. That won't work for many reasons, not the least of which is that federal involvement in an area traditionally left to the states distracts federal officials from their actual responsibilities, such as enforcing immigration laws.

Available federal resources shouldn't be used to combat local street crime that doesn't involve core national responsibilities.. More resources should be devoted to this and similar programs to have an even greater impact on the enormous problems of illegal immigration and gang crime.

Those who enter our country illegally are flouting our laws. To add insult to injury, those who join gangs and engage in violent crime not only show disrespect for our laws but also for the lives of U.S. citizens. The cooperation between ICE and local law enforcement is an effective, constitutional way to fight back.

Erica Little is a Legal Policy Analyst in the Center for Legal and Judicial Studies.