President Obama has a first name, Barack. Tags on diaries need to include this to link a diary to Barack Obama. After all, a bare link "Obama" could easily be Michelle (ma belle!). Even "President Obama" is potentially ambiguous as Malia is a very promising young person. In any case the convention for tags is to use first and last name without a title.
It's the most commonly used first name, too, which for the Republican contenders give us:
Newt Gingrich (not Newton)
Mitt Romney (not Willard)
Any trusted user can fix tags to reflect this but it would be lovely if authors would get there first.
There is nothing beyond the fleur de Kos.