Why would the E-4B be used as a transport for any US VIP ? As far as I was aware it was the command post used in a doomsday scenario to provide a 'Govt in the air' impervious to EMP's etc. Wouldn't the US Sec of Defence normally travel in a C40 or C32 ??
I always found the ghostly white of the E-4's matched their ominous purpose. They used to come in pairs to sit at Mildenhall during Presidential visits to the UK in the past.