BOB SCHIEFFER, moderator of the third presidential debate, noted that he had received more e-mail on immigration than on any other topic. The issue evokes strong opinions and emotions -- which may explain why neither candidate wants to talk about it much.

Hard though it is to remember, President Bush began this year by announcing an ambitious plan to reform this country's "broken" immigration laws. Among other things, he proposed a guest-worker program and a way for illegal immigrants to earn legal status. While we applauded aspects of the proposal, most notably its commitment to bringing the enormous underground labor economy into the sunlight, the president left many details vague. In subsequent months, he never clarified them. On the contrary: He dropped the immigration issue completely. The very notion of "earned legalization" for illegal immigrants caused an uproar among the Republican base, while many people who might have been natural supporters of the idea were unwilling to stand with Mr. Bush. During the third debate, the president made sure to say, "I don't believe we ought to have amnesty," just in case any doubters remained.

Sen. John F. Kerry, while not silent like the president, has been circumspect. He has stuck to his long-standing positions: He favors earned legalization, he has backed agricultural guest-worker bills in the Senate, and he has spoken, as every presidential candidate for the past several decades has, about "cracking down" on the borders and on employers who hire illegal workers. Yet Mr. Kerry gives few details, either on his Web site or in his public appearances. When asked about immigration, also in the third debate, he kept his answers brief, growing more eloquent only when he spoke of border controls, and he noted that "we now have people from the Middle East, allegedly, coming across the border." This is, presumably, wise politics: Emphasize border control and the work that needs to be done to halt illegal immigrants, rather than dwelling on the uncomfortable fact that millions of illegal immigrants live in this country and that something needs to be done with and for them too.

The candidates are reflecting the nation's increasingly conflicted attitude toward immigration. Although Americans are happy to eat the cheap food and to enjoy the cheap services provided by recent immigrants, they prefer hearing about border controls rather than earned legalization. Although Americans are happy to pay law enforcement officials to keep immigrants from crossing the border, they are also unbothered by the fact that thousands of agricultural, manufacturing and service businesses depend on their arrival. Squaring this circle may turn out to be one of the primary jobs of the next president. It would be useful to hear more from both candidates about how they intend to do it.

This is one in a series of editorials comparing the records and programs of the presidential candidates on important issues. Others can be found at www.washingtonpost.com/opinion/thechoice.