Affirmative action is one of those high-octane issues that Americans often are reluctant to discuss. But that didn’t stop the U.S. Supreme Court from deciding to revisit the subject, at least as it relates to university admissions.

The justices did the right thing in deciding to take on this thorny issue. They soon will have the chance to do right again by ruling that institutions of higher learning in America must have the discretion to take note of things like applicants’ race and ethnicity as they make tough decisions about whom to admit. They must do so fairly, of course, but with an eye toward expanding educational opportunity.

Now on the court’s docket are two cases that challenge admissions practices at the University of Michigan. Both cases were put together by the Center for Individual Rights, a group that opposes affirmative action. The center contends the university violates the equal protection clause when it denies admission to white students while accepting black and Hispanic students with lower grades and test scores. The university insists its admissions policies are both legal and thoughtfully conceived. It has been a long time since arguments like these have been made at the Supreme Court — 24 years to be exact. It was 1978 when the Supreme Court handed down its landmark ruling in University of California v. Allan Bakke. And even that decision was far from definitive. The court invalidated the “quota” that Bakke claimed kept him out of medical school and ordered him admitted.

But it also affirmed the legitimacy of race-conscious admissions as long as an applicant’s race was considered as one factor among many. Individual campuses were left to solve that riddle on their own, and it is no wonder that so many have ended up in court.

Enough of that. The Supreme Court needs to clarify the issue. It needs to state unequivocally that universities may consider race and ethnicity in admissions, and then establish parameters within which they may proceed.

With those rules in place, maybe Americans can focus on the real issue: What in the world is wrong with public education in America at the primary and secondary levels that it cannot produce enough minority students to matriculate to college campuses without the helping hand of affirmative action?