Agreed about the photoshopping. Look at the way the blue field on the flag is indented by OHO’s arm, the bottom of the flag chopped off, the strange perspective of the flag compared to the perspective of the chairs and women. It’s a very poorly done collage.
This was from the same event as the photo in question. You can clearly see the big flag behind Obama as he talks at about the 38 second mark. It is supported by a wooden stand. It isn't photoshopped.