Any sensible immigration reform would focus not just on keeping illegals out of the country, but also on why they're coming and how to get the estimated 11 million illegals already here out of the shadows. Yet last year the House whooped through a bill that expands enforcement and nothing else.

We doubt voters elected a Republican Congress to build walls along the Rio Grande and Canada and punish businesses for hiring willing workers. But since Representative James Sensenbrenner and other House GOP leaders have ignored President Bush's request for comprehensive reform, soberer types in the Senate will have to keep Republican restrictionists from running the party over a cliff.

For starters, the Senator's guest-worker program would require participants to leave the U.S. after six years and remain in their home country for an entire year before returning to the U.S. That kind of forced turnover could mean huge labor disruptions for U.S. businesses, and the likely result would be more illegal aliens, as some workers exit the program and enter the black market rather than returning home.

This is the same mistake the restrictionists made in 1986, when President Reagan signed a bill legalizing three million workers but didn't create a mechanism--dispensing enough green cards--for the economy to get the workers it needed in the future. Some 500,000 people continue to enter the U.S. illegally every year, and the strong economy and low jobless rate (4.8%) are evidence that these undocumented workers aren't "stealing" jobs but simply filling them.

The U.S. dispenses only about 10,000 green cards annually for unskilled workers. And by not providing enough paths to permanent residency for those who want to stay, we're setting ourselves up for another large illegal population down the road. Under current law, foreign workers in high-tech fields can extend their stay if an employer sponsors them for a green card. Why should the same rules that apply to Intel's engineers not also apply to Marriott's chambermaids and California's farm hands?

Like the House bill, Mr. Specter's proposal also includes over-the-top security measures like expanding the definition of "alien smuggling" to include church soup-kitchen operators and people who take in relatives who are here illegally. Mr. Specter would also create an army of federal agents and prosecutors to "investigate" immigration violations. But it makes little sense to start raiding businesses and driving foreigners further underground without first expanding the legal ways for the economy to get the workers it needs.

At least Mr. Specter isn't proposing to deport illegals already here en masse, which isn't practical in any case. But he still wants to create an 11 million-strong subclass of noncitizens who would be allowed to continue working in the U.S. but have little chance of ever receiving a green card. People in this new status would be subject to deportation if they're out of work for more than 45 days, which lays the foundation for all manner of exploitation. Workers need mobility and the freedom to quit unsatisfactory jobs.

In theory, Mr. Specter's proposal puts these current illegal residents on course for a possible green card. But the reality is that they would be placed at the end of a very long queue that already contains millions of people, and very few would ever see normal status in their lifetime because the annual caps make for a very slow-moving line.

As public policy, it's also hard to see the benefit of keeping 11 million largely Latino residents in permanent "conditional" status instead of allowing (and encouraging) them to become full-fledged members of American society. Relegating so many people to second-tier status sends precisely the wrong message about assimilating to U.S. norms, and which political party sends that message won't be lost on Hispanic voters.

None of this will appease the small but vocal "no amnesty" crowd, but restrictionists put forth no solutions other than greater militarization of the border and harassment of employers, which we know from experience won't work alone. If the real goal of immigration reform is to have people "obey the rules," let's make sure the rules are sensible.