No one bothered about century's warmonger (6)
I believe the answer is:
neocon
'warmonger' is the definition.
I know nothing about this answer so I cannot judge whether it can be defined by this definition.
'no one bothered about century's' is the wordplay.
'bothered' indicates an anagram.
'about' means one lot of letters goes inside another.
'century' becomes 'C' (common abbreviation).
'no'+'one'='noone'
'noone' is an anagram of 'neoon'.
'neoon' enclosing 'c' is 'NEOCON'.
Can you help me to learn more?
(Other definitions for neocon that I've seen before include "politician on the right" , "A supporter of the policies of President George Bush? (abbr)" , "Traditionalist" , "Right-wing American" , "A right winger" .)