The crackdown on illegal aliens has American employers resisting the federal government's aggressive enforcement of immigration laws, which has led to high-profile raids of leading companies in cities across the country.

With illegal immigration a highly charged political issue, Immigration and Customs Enforcement has stepped up in the past year its enforcement of existing laws barring the employment of illegal immigrants. Last year, agents arrested nearly 5,000 people in workplace raids, disrupting production schedules for hours of searches and questioning and leaving employers short of workers after the arrests.

The administration is also pressing ahead with its E-Verify program, requiring employers to compare Social Security numbers of new hires with a federal database. Now mandatory for federal contractors, the system requires the firing of workers whose numbers do not match. Employers object to the system since it is riddled with errors and could lead to legal immigrants and U.S. citizens being dismissed from jobs.

However, many states also require state contractors to submit to the screening as well in one of many anti-illegal-immigration measures being employed by states. Several states also revoke licenses of businesses that knowingly hire illegal immigrants while others fine and jail business violators. A few give terminated employees the right to sue if they are replaced by illegal aliens.

But, the New York Times noted, businesses are fighting back. An Arizona-enacted law last year revoking licenses of employers caught twice with illegal immigrants has already been modified once. An employers group has succeeded in putting on the November ballot an initiative to limit it further.

Oklahoma employers succeeded in getting a federal court order blocking a state law requiring businesses to check the federal database to verify the immigration status of new workers.

Ironically, the organized opposition by employers comes at a time when others decry the apparent discriminatory aspect of workplace raids that do not arrest employers, as recently noted by the Houston Chronicle. It reported that just 75 employers had been arrested from October through June.

Rep. Ted Poe, R-Texas, called it "a waste of time if we don't go after the business owners who are knowingly hiring illegals."

Homeland Security officials respond to the critics by noting that it can sometimes take years to build a case to prove an employer knowingly hired illegal immigrants while charges against undocumented workers are much easier to substantiate.

The tensions reflect the national mood and will continue until the country resolves its conflicts over immigration with national reforms.