Isn’t bowing usually akin to our handshakes - only more complicated? Anyhow, maybe he’s got a box set of DVD’s of the top Hollywood movies... /s
I don’t know if it’s the same thing as a handshake or not. I know when my family lived there, it was a common gesture but the bow was nothing like what Obama did. It was closer to a nod than a bend at the waist bow.