Because power corrupts, society's demands for moral authority and character increase as the importance of the position increases.
I think there ought to be some serious discussion by smart people, really smart people, about whether or not proliferation of things like The Smoking Gun and TMZ and YouTube and the whole celebrity culture is healthy.
I'm an advocate of the great Dr. Johnson, the English man of letters who said that patriotism was the last refuge of the scoundrel.