Patriotic tune the man composed (6)
I believe the answer is:
anthem
'patriotic tune' is the definition.
'the man composed' is the wordplay.
'composed' is an anagram indicator.
'the'+'man'='theman'
'theman' is an anagram of 'ANTHEM'.
(Other definitions for anthem that I've seen before include "The man for a popular song" , "Solemn song" , "National melody" , "Internationale?" , "National tune" .)