WASHINGTON -- It is a trap.

Republicans are now poised to oppose an accomplished Latina federal judge for the Supreme Court, further alienating Hispanic voters the GOP has recently driven away in droves. The main line of Republican criticism is likely to concern affirmative action -- which might provoke conservative extremists to predictable extremes and confirm an image of Republicans as the party of the male and pale.

President Obama's choice of Judge Sotomayor was not cynical; she exactly mirrors his judicial philosophy of "empathy." But it is still a trap.

Some traps should be avoided completely -- and there is a case for avoiding this one. The Constitution gives the president a decisive role in the nomination process. He deserves broad deference to his judicial choices. Sotomayor's story is inspiring; she is experienced and qualified. She has demonstrated a capacity to fairly apply the law -- for example, in upholding the rights of anti-abortion protesters. And, for goodness sake, she ended the baseball strike in 1995. Barring unforeseen ethical revelations, opposition to Sotomayor seems both politically risky and ultimately futile.

Yet Republicans must still enter the trap -- with open eyes and no expectation of gain -- not to defeat a nominee, but to maintain a principle.

The principle is simple: A court should be a place where all are judged impartially, as individuals. The Obama/Sotomayor doctrine of empathy challenges this long-established belief. It is not a minor matter.

As a young senator involved in judicial nomination debates, Obama showed no deference to presidential choices. Instead, he developed a theory that Supreme Court justices should favor socially unfavored groups. He opposed John Roberts for using his skills "on behalf of the strong in opposition to the weak." He criticized Samuel Alito for siding with "the powerful against the powerless." Obama made these distinguished judges sound monstrous because they stood for the impartial application of the law.

By Obama's empathy standard, Sotomayor is a natural choice. She has argued: "The aspiration to impartiality is just that -- it's an aspiration because it denies the fact that we are by our experiences making different choices than others." And these culturally conditioned choices are not just "different." She contends that a "wise Latina woman" will "more often than not reach a better conclusion than a white male who hasn't lived that life."

None of this is particularly controversial at Obama's University of Chicago or Sotomayor's Princeton. In elite academic settings, it is commonly asserted that impartiality is not only a myth, but also a fraud perpetuated by the privileged. Since all legal standards, in this view, are subjective and culturally determined, the defenders of objectivity are merely disguising their exercise of power. And so the scales of justice -- really the scales of power -- need to be weighted by judges to favor the "weak" and the "powerless."

Sotomayor's decision in the case of Ricci v. DeStefano is disturbing because it seems to affirm this judicial philosophy. The New Haven, Conn., firefighters who studied for and passed a promotion examination (including a Hispanic) were denied a benefit they had earned, entirely because of their skin color. Because they were not part of a group deemed "powerless," they were rendered powerless as individuals. Empathy turns out to be selective empathy -- not for human beings, but for social groups. Just imagine the frustration and anger of standing before a federal judge who is predisposed against your claims for racial reasons of any sort. A federal court should be one place where every individual -- black or white, pauper or Rockefeller -- is exactly equal in rights and dignity.

Racial injustice against African-Americans is still alive in America, and the wounds and disadvantages of slavery and segregation linger. The vision of an entirely colorblind society can itself be a kind of blindness, ignoring continuing struggles and continuing bigotry. Institutions should be able to address past and present injustice through some forms of affirmative action, including the aggressive recruitment of minorities and the use of race as one factor among many in subjective admissions and hiring decisions. But denying earned benefits because of race alone is an injustice that will never solve an injustice.

Concerns about the doctrine of empathy will not defeat Sotomayor -- and perhaps they should not defeat her. Obama democratically earned his choice, as other presidents have done. But the problems raised by selective empathy require a substantive (not harsh or personal) national debate -- and this requires Republicans to carefully, warily, enter Obama's trap.