I tell you why even if bobby d had a body guard why he got a gun of your own.
These guys are deterents.
Are they stupid enough to step in front of a gun to save your ass 
?
You've never heard of the Secret Service?
DeNiro's a hypocrite. He's a bleeding heart liberal in every way, shape and form. He's anti-gun, except when it comes to himself. He has money for bodyguards and he employs a full-time driver who's licensed to carry himself.
He needs to carry a gun like you need to go off your Thorazine.