Rational, finding soldier in pub (7)
I believe the answer is:
logical
'rational' is the definition.
('logical' can be similar in meaning to 'rational')
'soldier in pub' is the wordplay.
'soldier' becomes 'gi' (government issue or general issue).
'in' indicates putting letters inside.
'pub' becomes 'local' (I've seen this before).
'gi' put into 'local' is 'LOGICAL'.
'finding' acts as a link.
(Other definitions for logical that I've seen before include "entirely reasonable" , "Well reasoned" , "Correctly thought out" , "Clearly and soundly reasoned" , "Sound" .)