>Robert Kagan, husband of Victoria Nuland, argues that it is better “for the U.S to seek confrontation” when the odds of nuclear annihilation are “extraordinarily small.”
Kagan is now a surname, but the term 'kagan', or 'khaqan' comes from Central Asia. It used to mean 'king', or ruler among the Khazars.
https://banomcleod.wordpress.com/2017/06/07/kagan-and-khazaria/
The supreme sovereign was the kagan, the high priest, but the actual ruler was the vicegerent or assistant kagan.
http://www.encyclopediaofukraine.com/display.asp?linkpath=pages%5CK%5CH%5CKhazars.htm