Huckabee, speaking at a session sponsored by the Christian Science Monitor, criticized Obama for being "clearly out of sync with the public." This assertion is both debatable - Huckabee cited the 33 states where voters have approved measures to prohibit same-sex marriage; recent polls show the public closely divided - and irrelevant.
If the president and the Justice Department are correct that Section 3 of the act is unconstitutional - as I think they are, for reasons explained below - opinion polls are as meaningless as they would have been on the question of school desegregation in 1954.
The more interesting part of Huckabee's argument was his immediate and illogical pivot to the "quantified impact of broken families."
He pointed to a "$300 billion dad deficit in America every year. That's the amount of money that we spend as taxpayers to pick up the pieces because dads are derelict in their duties and they're not raising their kids and supporting them. . . . One of the reasons I came to the conclusion was not for an evangelical reason. It was seeing a lot of money that we spend as a state was spent in picking up the pieces of people whose lives were broken because their families were dysfunctional or shattered."
Cue Daniel Patrick Moynihan. "He understood the economic reality of out-of-wedlock children," Huckabee said.
Except - isn't this an argument for same-sex marriage, not against it?
Unless you believe that the absence of the right to marry will prevent gays and lesbians from having children - and it doesn't seem to be - you ought to be celebrating their desire to form stable unions and subject themselves to clear legal responsibilities. Gays and lesbians are clamoring for the right to avoid the very societal ill that Huckabee decries.
Looking at the world through a Huckabean lens, the president's move affirms states' rights. After all, Obama is simply saying that the federal government will from now on respect a state's definition of marriage - even if it encompasses same-sex marriage.
If Huckabee makes, albeit inadvertently, a good argument for gay marriage, Chief Justice John Roberts offers a solid precedent for Obama's decision not to defend the law's constitutionality.
As Attorney General Eric Holder said in his letter explaining the change of position, gay men and women have "suffered a history of discrimination" and "a growing scientific consensus accepts that sexual orientation is a characteristic that is immutable."
Those factors would subject laws discriminating on the basis of sexual orientation to "heightened scrutiny," the same as for distinctions based on gender. Under this standard, defending the law would require the government to show that the discrimination is "substantially related to an important government objective." None exists, Huckabee's false linkage notwithstanding.
The harder legal question is whether the president was justified in taking the extraordinary step of declining to defend a federal statute. "We can't have presidents deciding what laws are constitutional and what laws are not," said Sen. Scott Brown, Republican of Massachusetts. "That is a function of the judicial branch, not the executive."
The judicial branch will get the final say, and the president promised to enforce the law in the interim. Still, you don't want this happening very often. I don't want this happening if a Republican president is called on to defend the new health-care law. It should be, as former solicitor general Seth Waxman has written, "a rare and solemn act."
Which brings me to Roberts, as a lawyer in the solicitor general's office during the George H.W. Bush administration. Roberts not only declined to defend a congressionally mandated program to give minority applicants preferences in obtaining broadcast licenses - he filed a brief urging the justices to strike it down.
The president's actions here are more restrained - and more justified. The law has changed significantly since the Defense of Marriage Act was passed in 1996. Back then, the high court had ruled that states could criminalize homosexual conduct. In the years since, the justices have overruled that decision. Numerous courts have found constitutional protection for gay rights.
"When an act of Congress has been challenged, the solicitor general ordinarily puts a heavy thumb on the scale," Waxman wrote. In this case, Obama was wise to remove it.