A desire to burn borders of pretty country (9)
I believe the answer is:
pyromania
'a desire to burn' is the definition.
'borders of pretty country' is the wordplay.
'borders of' suggests removing the centre.
'country' becomes 'romania' (Romania is an example**).
'pretty' with its middle removed is 'py'.
'py'+'romania'='PYROMANIA'
(Other definitions for pyromania that I've seen before include "Obsessive desire to start fires" , "Obsession with burning things" , "lighting up for fun?" , "Fire-raising compulsion" , "Burning desire" .)