Command to invade indistinctive territory close to another country (10)
I believe the answer is:
borderland
'territory close to another country' is the definition.
(territory on a border)
'command to invade indistinctive' is the wordplay.
'command' becomes 'order' (order is a kind of command).
'to invade' is an insertion indicator.
'indistinctive' becomes 'bland'.
'order' inserted within 'bland' is 'BORDERLAND'.
(Other definitions for borderland that I've seen before include "marches" , "region close to frontier" .)