US soldier in column showing upturn in sense (5)
I believe the answer is:
logic
'sense' is the definition.
(logic is a kind of sense)
'us soldier in column showing upturn' is the wordplay.
'us soldier' becomes 'gi' (I've seen this in other clues).
'in' indicates putting letters inside.
'column' becomes 'col'.
'showing upturn' shows that the letters should be reversed in order.
'col' back-to-front is 'loc'.
'gi' going inside 'loc' is 'LOGIC'.
'in' acts as a link.
(Other definitions for logic that I've seen before include "Chain of reasoning" , "Rationale ?" , "Reasoned judgement" , "Reasonable judgement" , "The science of reasoning from cause to effect" .)