Soldiers protecting domestic fortifications (8)
I believe the answer is:
parapets
'fortifications' is the definition.
(parapet is a kind of fortification)
'soldiers protecting domestic' is the wordplay.
I cannot quite see how this works, but
'soldiers' could be 'ra' (Royal Artillery) and 'ra' is found within the answer.
This may be the basis of the clue (or it may be nonsense).
Can you help me to learn more?
(Another definition for parapets that I've seen is " Low protective walls along edges of roofs or balconies".)