He was ID’d a while back. USSS, they say.
He keeps in close proximity on the campaign plane, too.
http://binaryapi.ap.org/a8530eb056314a94bf5cb8ff16bc8a94/preview/AP16305722202419.jpg?wm=api&ver=0
USSS? FWIW, I doubt it. Or, if he is, he’s got a unique job classification. A recent one.