Soldiers struggle with critical examination (6)
I believe the answer is:
review
'critical examination' is the definition.
(I've seen this before)
'soldiers struggle with' is the wordplay.
'soldiers' becomes 're' (Royal Engineers).
'struggle' becomes 'vie' (to vie is to struggle or contend with).
'with' becomes 'w' (short for with).
're'+'vie'+'w'='REVIEW'
(Other definitions for review that I've seen before include "Critique of book or play" , "criticism" , "A critique or commentary on play or film" , "Take stock" , "General survey of a plan" .)