President Obama did not end the "birther" movement today. Hours after the president released his long-form birth certificate—years after releasing the short-form one that proved he was a citizen—the issue had already evolved. Republicans who'd been on the hook demanding proof of his citizenship wondered why it took so long. People with too much time on their hands—in other words, the majority of people surfing the Internet for this kind of stuff—were combing the document for proof of forgery.Weigel's conclusion is that Obama has shown himself willing to engage with buffoons like Trump, meaning the conspiracy theorists will keep coming now that they know they have a soft target. I sort of agree with that. It probably would have been better to keep being dismissive of birthers, rather than to give them any sort of credence. As the last few days of innumerable (debunked) attempts to prove the birth certificate a forgery, the people who subscribe to birtherism continue to do so in the face of all evidence to the contrary for a very simple reason: because it suits them. If yesterday's scrap between yours truly and Dad29 proved nothing else (apart from the implacable differences between the two of us), it is that birtherism is just a tool for those who just want to hurt the president (guilt by association with negative ideas works too), whether they believe it or not.* In fact, those people are very willing to shrink from explicit birtherism, if only to look more "reasonable." Fred Dooley's email to Zach W. of Blogging Blue is a great case in point.
So Obama did not end birtherism. He did end one era of conspiracy theories about him—the fifth era, by my count. And maybe all he did was make sure the sixth era got started with as loud and embarrassing a bang as possible. If you understand how this started, and who played the biggest roles in elevating it, maybe you can also understand why it's not going to end.
The fact of the matter is that there simply is no evidence whatsoever that could convince them, because disproving one set of claims just gives rise to a claim that the evidence is forged, or else the conspiracy theorists move on to new and different theories. The 9/11 Truth movement is a perfect analog. Either way, it is belief in a conspiracy because it fulfills the needs of the believer, even if the believer has to change justifications in order to continue his or her belief. What's the point of engaging with yahoos who can't be persuaded anyway?