Little picture books capturing opponents following international (5)
I believe the answer is:
inset
'little picture' is the definition.
'books capturing opponents following international' is the wordplay.
'books' becomes 'NT' (abbreviation for New Testament).
'capturing' means one lot of letters goes inside another.
'opponents' becomes 'se' (I can't explain this - if you can you should give a lot more credence to this answer).
'following' says to put letters next to each other.
'international' becomes 'i' (abbreviation eg in IMF).
'nt' placed around 'se' is 'nset'.
'nset' put after 'i' is 'INSET'.
Can you help me to learn more?
(Other definitions for inset that I've seen before include "day for teachers" , "Not taking proper care" , "Small picture placed within a larger one" , "Reduced image" , "Magazine feature" .)