It has been a historic 24 hours, with marriage equality rejected in North Carolina and embraced by the president of the United States.

“I am gratified that the president has thrown his personal support and the authority of the presidency behind the goal of justice, equality, and decency for all citizens,” said Ted Olson, founder of the Federalist Society and former Bush administration solicitor general.

Olson gained fame for his pioneering partnership with David Boies, his one-time professional rival in Bush v. Gore who joined with him to argue that California’s Prop 8 gay-marriage ban is unconstitutional.

I called Olson on Wednesday to get the conservative legal leader’s take on the North Carolina gay-marriage ban at the ballot and the way it sets up a Supreme Court showdown, possibly as early as 2013—no matter who is president.

Olson has stern words for his fellow conservatives who flooded the polls on Tuesday, making North Carolina the 30th state to enshrine a ban on gay marriage in its state constitution.

“It is very sad to me that people who belong to the party of Abraham Lincoln are resisting so strenuously the equality and decency and integrity and treatment of our gay and lesbian brothers and sisters,” Olson said. “This seems to be one of the last major civil-rights battles of our country. And for people in our country to come out in numbers like this and say, ‘Well, we don’t want the persons next door—who are decent, God-fearing, taxpaying, obeying-the-law citizens who simply want to have happiness like the rest of us’—to say ‘No, I have that right and you can’t have it.’ That just seems mean to me.”

The rollback of civil unions and domestic partnerships in North Carolina is a particular legal red flag to Olson. “This is a law, like California, that withdraws existing rights from people based upon their sexual orientation,” he said. “It withdraws rights and privileges that gay and lesbian citizens have had in North Carolina for some time now. That is one of the bases on which the Ninth Circuit specifically struck down Proposition 8.”

The other constitutional question is whether civil rights can be put to a popular vote. “There are a number of cases that went to the Supreme Court involving schools in North Carolina because of resistance to desegregation decrees,” Olson said. “How many citizens would have voted to continue separate-but-equal schools, if you’d put that to a vote in 1954? In fact, in 1967, there were 14 states that prohibited interracial marriages, indeed made interracial marriages a felony, and the Supreme Court struck down those laws unanimously in 1967.”

In other words, history can be our guide, offering the ability to view our political debates with a sense of perspective.

Indeed, the current trajectory for the gay-marriage debate seems destined for the Supreme Court, Olson said. Right now, the Ninth Circuit decision declaring Prop 8 unconstitutional is being contested by the losing party, which could result in the full 25 judges rehearing the case. If that motion is denied, it presumably will head next to the Supreme Court, which could happen as early as the fall docket for deciding to take the case or not.

President Obama’s endorsement of same-sex marriage is risky politically in swing states like North Carolina and Virginia. But his view is gaining support, and not just in national polls. “There is a movement among conservatives, particularly conservatives with a more libertarian streak, to move in the direction of supporting the rights of gay and lesbian citizens. It’s moving pretty fast actually but it’s not moving fast enough,” Olson said. “And as I read the results of North Carolina I feel very, very sad for the citizens who are victims of that measure. I also feel badly for the citizens who voted for it because someday they’re going to say, ‘I was wrong; I should not have done that.’”

This is a profile-in-courage moment for President Obama, but it comes with considerable political risks. The decision recalls a moment of White House history that came to light in the fourth volume of Robert Caro’s LBJ biography. When cautioned by advisers that advancing civil rights might be moral but would not be politically pragmatic in 1964, the new president leaned back in his chair and said, “Well, what the hell’s the presidency for?"