Abraham Lincoln is remembered today for freeing the slaves. But he didn't start out with that policy, and he didn't get there quickly. He reached his ultimate position only by slowly and painfully "evolving" -- while blacks waited and suffered in bondage.
When he came out for same-sex marriage, Obama won praise from gays, liberals and libertarians who have supported same-sex marriage all along. But he has also gotten sharp criticism from both left and right.
The Log Cabin Republicans, representing gays and lesbians, called the president "callous" for not speaking up sooner. One blogger jeered that if Obama "were on the Supreme Court, he would vote against us. Obama supports same-sex marriage, but he sees no constitutional mandate."
The conservative New York Post accused him of "a carefully calculated political ploy, designed for maximum political effect to shore up an increasingly unenthusiastic voter base" -- the "epitome of cynicism."
It's not hard to make the case that Obama is a cold-blooded operator keenly interested in his own political fortunes. If he were principled, he would have stuck to the pro-gay marriage position he took in 1996. If he were fully committed to equal rights, he wouldn't agree to let states ban same-sex unions.
And what has he actually done to legalize gay marriage? Nothing. In his ABC News interview Wednesday, Obama merely said that "personally," he's for it. He took no concrete action.
Nor does he plan to. The next day, he stressed, "I'm not going to be spending most of my time talking about this." His shift could be taken as empty symbolism.
But if you think Obama has been slow, ineffectual and averse to political risks, you should have seen Lincoln's handling of slavery. Through the haze of history and myth, it's hard to remember that on this matter, Lincoln was often anything but inspiring.
"I have no purpose, directly or indirectly, to interfere with the institution of slavery in the states where it exists," he declared in 1858, and he reiterated that position in his first inaugural address.
Lincoln was anti-slavery in the sense that he opposed allowing it in new states and territories and thought halting its spread would eventually cause it to die. But he was in no hurry. Slavery, he said, "might be let alone for a hundred years, if it should live so long, in the States where it exists."