At any Presidential appearance I've ever attended -- and that's been a
fair number in getting close to 40 years in the DC area -- there is
ALWAYS a getaway team on alert -- usually one or two armored limos, a
Secret Service Suburban or the like, and local police.

The pretty well-known drill is that someone yelling "GUN!" on the Secret
Service frequency means GET HIM OUT OF HERE RIGHT NOW!

Too much security for a position with ceremonial duties only.