In 1996, Congress passed the Defense of Marriage Act by huge bipartisan votes — 342 – 67 in the House and 85 – 14 in the Senate. President Bill Clinton signed the measure into law.

Now, the Obama administration says DOMA, which permits states to refuse to recognize gay marriages from other states and creates a federal definition of marriage as the union of one man and one woman, is unconstitutional. In Boston recently, Stuart Delery, an attorney for the Justice Department’s Civil Rights Division, urged the 1st Circuit Court of Appeals to find DOMA violates the Constitution by discriminating against gays and lesbians. “I’m not here to defend (the law) on any standard,” Delery told the court.

What was striking about Delery’s request that a federal court strike down DOMA was that at virtually the same time, President Obama was railing at the very notion that a federal court would strike down any law passed by Congress.

“I’m confident that the Supreme Court will not take what would be an unprecedented, extraordinary step of overturning a law that was passed by a strong majority of a democratically elected Congress,” Obama said about the arguments over Obamacare before the nation’s highest court. The danger presented in the health care case, the president continued, is that “an unelected group of people would somehow overturn a duly constituted and passed law.”

Obama immediately ran into a barrage of questions. How can the Supreme Court overturning a law be “unprecedented” when the court has done it more than 150 times in U.S. history? And does the president even recognize the court’s authority to rule on the constitutionality of laws passed by Congress?

Backtracking, Obama said the next day that “the Supreme Court is the final say on our Constitution and our laws, and all of us have to respect it.” He also claimed, without convincing many people, that he called the Obamacare case “unprecedented” because it’s been awhile since the court overturned “a law that was passed by Congress on an economic issue, like health care.”

But what about that “strong majority”? When reporters pointed out that Obamacare passed the House by a narrow margin of 219 – 212, White House spokesman Jay Carney quickly revised “strong majority” to simply “majority.”

But all that backing and filling — including Carney’s claim that Obama was misunderstood “because he is a law professor” — was before the DOMA arguments made news. If the president was so concerned about a court overturning a duly constituted law passed by a democratically elected Congress, why was he urging a small group of unelected judges to strike down DOMA, a measure that won passage by a far greater margin than Obamacare?

The answer is, of course, that the administration is making a political argument for its positions, not a legal one. And perhaps counterproductively, the president’s decision to bring up Obamacare’s history in Congress could end up reminding the public of the tangled circumstances of its passage. Even with a huge majority in the House, Democrats barely passed the bill in the face of bipartisan opposition. And in the Senate, Obamacare succeeded as the result of a set of freakish circumstances that allowed Democrats to pass an unpopular measure into law.

Those circumstances included the wrongful prosecution of a Republican senator (Ted Stevens), resulting in his seat going to a Democrat; the defection of another Republican senator (Arlen Specter) to the Democrats; and a change in one state’s laws (Massachusetts) to allow a Democratic governor to immediately appoint a Democrat to succeed the late Sen. Ted Kennedy and give the Senate a 60-vote Democratic supermajority. And then there were the policy payoffs to some Democratic senators who were undecided about the bill. Even then, Democrats held a filibuster-proof majority in the Senate for just 134 days before Massachusetts elected a Republican senator, Scott Brown, who ran specifically on the platform of stopping Obamacare. But in those 134 days, Democrats managed to pass an unpopular bill into law without a single vote to spare.

Now, the timing of the arguments over Obamacare and DOMA has revealed the flexibility of the administration’s arguments over constitutionality. And the flap over Obama’s remarks is just a preview of what is coming when the court issues its decision on Obamacare this June.

A decision on DOMA, which has not yet arrived at the Supreme Court, lies in the future. But if those arguments come when Barack Obama is president, perhaps DOMA’s defenders will remind the administration of the president’s respect for duly constituted and passed laws.