Laugh at revolutionary socialist vision falling short (6)
I believe the answer is:
deride
'laugh at' is the definition.
(I've seen this in another clue)
'revolutionary socialist vision falling short' is the wordplay.
'revolutionary socialist' becomes 'der' (I can't explain this - if you can you should give a lot more credence to this answer).
'vision' becomes 'idea' (I've seen this in another clue).
'falling short' means to remove the last letter.
'idea' with its last letter removed is 'ide'.
'der'+'ide'='DERIDE'
Can you help me to learn more?
(Other definitions for deride that I've seen before include "Laugh at or make fun of" , "Knock" , "Speak of with contempt" , "Mock, scorn" , "'Mock, sneer at (6)'" .)