TEH OBMABAMS ARE RASSISSTZ!!! TEH DOGZ BLACK!!!
With that insightful political commentary out of the way, is it my imagination, or has no president in the last 40 years had a huge, shit scary dog? Honestly, why not? Great imagery: Powerful animal controlled by powerful man kinda stuff. Go for a Grey Wolf even! They're a large pack oriented breed, like StBernards or Alsatians. They're usually way more affectionate to their pack members than annoying little yappers, too.