World leaders that shout and argue have become sour (6)
I believe the answer is:
saturn
'world leaders that shout' is the definition.
'Saturn' can be an answer for 'world' (Saturn is another planet). I'm not certain of the rest of the definition.
'argue have become sour' is the wordplay.
'argue have' becomes 'sa' (I can't explain this - if you can you should give a lot more credence to this answer).
'become sour' becomes 'turn' (I've seen this in another clue).
'sa'+'turn'='SATURN'
'and' is the link.
Can you help me to learn more?
(Other definitions for saturn that I've seen before include "The second largest planet" , "Turn as a planet" , "Giant planet" , "tried to pass vessel" , "Roman god - gas giant" .)