Proponents of equality have reason to both cheer and cry this week.

This week, in a series of rulings, the Supreme Court laid bare once more a continuing divide in this country about the role and limits of government in ensuring — or denying — equality.

In the University of Texas at Austin affirmative action case, the Voting Rights Act case and the same-sex marriage cases, the court drew a line between policies that explicitly articulate exclusion and those that implicitly and effectually remedy exclusion — both current and historical.

Proponents of racial diversity were on the losing end of those rulings, and same-sex marriage proponents were on the winning end.

The court set a higher bar for including race as one factor among many in university admissions and struck down a key provision of the Voting Rights Act. But it also voided the Defense of Marriage Act and declined to decide the Proposition 8 case, effectively allowing same-sex marriage in California.