Protective garment for entering borders of Afghanistan (5)
I believe the answer is:
apron
'protective garment' is the definition.
(apron is a kind of protective garment)
'for entering borders of afghanistan' is the wordplay.
'for' becomes 'pro' (I've seen this before).
'entering' means one lot of letters goes inside another.
'borders of' suggests removing the centre.
'afghanistan' with its middle taken out is 'an'.
'pro' placed into 'an' is 'APRON'.
(Other definitions for apron that I've seen before include "stage perhaps" , "Domestic protection" , "Extension of stage in front of curtain" , "Cook's protector" , "Projecting stage" .)