Times is coming in to damage Mirror's lead as leftie stuff (7)
I believe the answer is:
marxism
'leftie stuff' is the definition.
I can't judge whether this defines the answer.
'times is coming in to damage mirror's lead' is the wordplay.
'times' becomes 'x' (multiplication sign).
'coming in to' means one lot of letters goes inside another.
'damage' becomes 'mar' (to mar is to spoil or damage).
'lead' suggests taking the first letters.
The first letter of 'mirrors' is 'm'.
'x'+'is'='xis'
'mar'+'m'='marm'
'xis' placed into 'marm' is 'MARXISM'.
'as' is the link.
Can you help me to learn more?
(Other definitions for marxism that I've seen before include "Political doctrine" , "Left-wing ideology" , "Left-wing system" , "Basis of communism" , "Left-wing philosophy" .)