Where's the Birth Certificate?, Jerome Corsi's ill-timed birther manifesto, has hit bookstores — just weeks after President Obama released his long-form birth certificate in an attempt to silence conspiracy theorists. But Obama's still pushing back. His campaign is now hawking "Made in the USA" T-shirts featuring a smiling Obama on the front, and his long-form birth certificate on the back. The campaign says the tees, available for a $25 donation, serve as mobile fact-checks to further undermine Corsi and other birthers. But isn't t-shirt warfare beneath the presidency?

This is "commercialism at its finest": Obama wrung some decent jokes out of the birther issue, and if he's "found a new way to profit from birtherism," good for him, says Kevin Douglas Grant at TruthDig. It's not like the release of his long-form birth certificate completely killed the fringe movement. Indeed, more than a third of Americans still claim to be skeptical. Funny T-shirts are "a clever (if risky) approach to this fiasco."

"Barack Obama: He's got the T-shirt to prove it"

Obama is shamelessly milking the issue: This isn't about refuting Corsi, says Stu Burguiere at The Blaze. "Obama LOVES birthers." Every time birtherism comes up, Obama wins, and this is just one more way to keep the faux controversy alive. Seeing him raise money off birtherism would be less galling, though, if he hadn't already hammered home how silly the whole thing is. When "did his schedule open up for silliness?"

"Obama + Birth certificate = Shameless"

Birthers may profit, too: This is "a business-savvy move that may even force Donald Trump to smile," says Josh Voorhees at Slate. But while the shirts may drum up some Obama campaign cash, they could also boost Obama's target's cause. With all the continued attention on this debunked conspiracy theory, Corsi's book sales are "trending up."

"Obama campaign cashes in on birther-mania"