My guess is that the Secret Service nixed any thought of a cross country bus tour, and probably had chit fits about the idea of using a bus period. It has always been the practice to ship the president's & his family's vehicles & at least those of his immediate security detail by the USAF, & they guarrantee that no one has had access to them & the aircrafts, a point of pride for the USAF. On this one the kid from Illinois gets a pass from me.
be safe, enjoy life, journey well
OFC, Mo. Chapter