### Clue: Less experienced party leader brought back before September 1939? (3-3)
### Answer: PRE-WAR 
 ### Explanation: Definition: before September 1939
 **Reversal of**(… brought back) [ RAWER(less experienced/greener) + **1st letter of**(… leader) "party" ].
Defn: Period before the start of World War 2.