Barack Obama has put the presidential seal on same-sex marriage, illustrative of the paradigm shift taking place in communal discussion of this volatile social issue.

We believe the president’s endorsement is long overdue.

The debate over same-sex marriage, and the attendant talking points wielded by both sides, have long been voiced in this newspaper and elsewhere. We do not need to revisit them except to emphasize a few key facts.

For one thing, the president’s comments have changed nothing yet. No state or federal laws have flipped in their wake. However, the public reaction to the comments, especially in the political realm, suggest that we have indeed reached a tipping point.

Many Republican leaders criticized Obama not for the content of his comments, but for their timing and perceived political motivation. How’s that for a shift? Only four years ago, opposition to same-sex marriage was a plank in the Republican Party platform.

Social conservatives and Orthodox Jewish leaders criticized the president, but as our article on page 10 points out, in the case of the Orthodox Union, the criticism was restrained and coupled with praise for the president’s awareness of religious sensibilities on the issue.

Elsewhere in the Jewish world, the reaction has been almost entirely positive. The Anti-Defamation League and the Reform movement’s Religious Action Center, among others, praised the president’s remarks.

Same-sex weddings have already been sanctioned by the Reform, Reconstructionist and Renewal movements, and the Conservative movement gives rabbis the choice whether to perform same-sex commitment ceremonies.  The Orthodox movement prohibits same-sex marriage, citing Jewish law.

The core arguments permitting same-sex civil marriage — arguments we agree with — primarily have to do with fundamental fairness in American society. It is wrong to grant certain rights to one set of citizens while denying them to another. It is wrong to put those rights up to a popular vote. Had this been done in the Deep South 50 years ago, desegregation would never have occurred.

Besides, granting civil marriage licenses to same-sex couples in no way infringes on the rights of religious institutions to perform wedding ceremonies or not.

It’s a matter of civil, not religious, law.

The states and the courts will continue to hash out this issue for years to come. Strong feelings persist on both sides, but Americans are already marrying members of their own sex, and will continue to do so. They should have that right, as a matter of law.

We applaud the president for giving the cause a tremendous boost.