Bob Somerby of The Daily Howler objects to the liberal conventional wisdom that, as the New York Times put it, “It is inconceivable that this campaign [birtherism]… would have been conducted against a white president”:

We think it was a remarkable statement because somewhat similar campaigns already have been conducted against white candidates. A somewhat similar campaign was conducted in 1988 against Candidate Michael Dukakis, for instance. After that, strains of the same ethnic/nativist cards were played against Candidate Kerry in 2004.

When I noted this point in a tweet earlier today, several readers objected, arguing that attacking someone’s eligibility for office is different from calling them “un-American”:

It’s a fair point. However, we need to be careful about the comparisons that we make in thinking about this question. As Somerby notes, Obama is different from other presidential candidates on other dimensions than race. In particular, he has a unique life story:

Let’s be clear: No one has ever been slimed in the exact same way Obama has been slimed. Reason? No other Democrat’s life story ever presented the same opportunities. Before Obama, no president or presidential candidate ever had a father from an exotic foreign country; no such candidate had ever been born in our most distant and exotic state.

For Obama’s race to be the cause of the birther critique, we would need to believe that a white presidential candidate with a foreign parent who spent much of his childhood overseas would not have his eligibility for office questioned. Is this plausible? Maybe, but I don’t think it’s “inconceivable” that a similar attack would have been launched at a white Democrat with Obama’s background.

None of this is to say, of course, that racial attitudes haven’t contributed to the acceptance of the myth among the public. Sadly, there’s lots of evidence that racial attitudes play an important role in people’s feelings about Obama. I would imagine that the same holds true for beliefs about his birth as well.

Update 5/6 2:24 PM: As Rob points out in comments, we do have a historical comparison — Chester A. Arthur, whose father was Irish. Here’s the Associated Press:

Nearly 123 years after [Arthur’s] death, doubts about his US citizenship linger, thanks to lack of documentation and a political foe’s assertion that Arthur was really born in Canada – and was therefore ineligible for the White House, where he served from 1881 to 1885.

Long before “birthers” began questioning the citizenship of President Obama, similar questions were raised about the early years of Arthur, an accidental president who ascended to the job after President James Garfield was assassinated.

“It’s an old rumor that won’t die, political slander,’’ said John Dumville, who runs Vermont’s historic sites and knows well the legend…

[T]he Arthur birthplace question came up before the Internet was around to spread such theories.

Known as Vermont’s “other president’’ – Calvin Coolidge was born in Vermont – Arthur was the son of a Baptist minister whose first assignment was this small town of 1,916 people in the heart of northern Vermont dairy country.

He was born Oct. 5, 1829, but later in life, he lied about the year. Even his gravestone lists 1830, though Arthur family bibles at the Library of Congress in Washington say 1829.

The family moved often, and by 1835 had left Vermont. Arthur went on to become a teacher, lawyer, and political operative, serving as quartermaster general for the state of New York during the Civil War and later Collector of the Port of New York, appointed by President Ulysses Grant.

The focus on his place of birth became an issue in the 1880 presidential campaign, when Arthur was tapped to be the running mate for Garfield.

According to historical accounts, Republican bosses wanted him to provide proof of his birthplace, but he never did.

Democrats, meanwhile, hired a lawyer named Arthur Hinman who sought to discredit Arthur, alleging that he was born in Dunham, Quebec, about 47 miles north of Fairfield. Hinman traveled to Vermont and Canada to research Arthur’s past, eventually concluding that Arthur was born in Canada but appropriated the birth records of a baby brother who was born in Fairfield, but died as an infant.

He later incorporated the findings into a book titled “How A British Subject Became President of the United States.’’

Arthur, who served from 1881 to 1885, never publicly addressed the allegation.

Update 5/6 2:44 PM: UNL political scientist Mike Wagner notes that being Irish in the 1880s made Arthur a racial outsider, which is true. Arthur isn’t a perfect comparison (we would need a white non-ethnic candidate), but the story certainly suggests that birther-type arguments are not just the result of a candidate being black.

Update 5/6 3:32 PM: John McCain’s qualifications for the presidency were also discussed as a result of him being born in the Canal Zone, though it never became a salient issue during the 2008 campaign.

[Cross-posted at HuffPost Pollster]