You could show the media his long form birth certificate with his original hoof print notarized in Hell and they wouldn't care.
At this point, busting him for not being an American (he never was) makes about as much sense as busting the Bent One for getting a Lewinski.
Hit him on the big stuff: ObamaCare / Libya / Contempt of Congress for Pete's sake.
LET’S DO ALL OF IT.