We’ve gotten a lot of good answers to our definitional question about birtherism. (And don’t tell Zack but I seem to be coming out on top.) But the most nuanced grasp of the question seems to come from TPM Reader CC …
I disagree with Zack’s assessment of natural-born-citizen Birthers vs. Kenyan-born Birthers being different entities. I read the freerepublic birther threads with great relish, and I can assure you that NBC-obsessed and Kenyan-born Birthers freely collaborate and trade ideas.
In fact, there are other types of Birthers beside those two; there are those who believe that Obama is in fact qualified to be president, but that his birth certificate contains information that would deviate from or dilute the public biography of the man–something like his father being Frank Marshall Davis, or his race being listed as White on the original certificate. There are also Birthers who believe that Obama was born in the US, but has raised as the ultimate Manchurian Candidate mole, by socialist/Muslim overseers. There are even Birthers who believe that the great secret of his birth is that he is one of a set of twins, for reasons I haven’t been able to entirely puzzle out.
I see Birthers as a manifestation of the classic type of conspiracy theorist. They constantly evolve their theories to fit whatever tidbit has most recently piqued their interest, whether it be the newest announcement from the Hawaii Department of Health, or whatever forged Kenyan birth certificate has surfaced recently. Compare them with Kennedy assassination theorists: some think the Mob did it, some think the CIA did it, some think it was LHO with assistance from the KGB. In the end, the small differences don’t matter as much from the outside. The fever swamp still looks like a fever swamp to anyone standing outside of it.
For a great example of the cross pollination and internal hostility this debate has created among conservatives, check out this thread on freerepublic, where you can see all the different Birther types (and their right-wing betes noir) co-mingling and swapping ideas and insults.