Strength of current making a politician, European, rant (8)
I believe the answer is:
amperage
'strength of current' is the definition.
(I've seen this before)
'a politician european rant' is the wordplay.
'politician' becomes 'MP' (Member of Parliament).
'european' becomes 'E' (abbreviation e.g. EU).
'rant' becomes 'rage' (I can't explain this - if you can you should believe this answer much more).
'a'+'mp'+'e'+'rage'='AMPERAGE'
'making' is the link.
Can you help me to learn more?
(Other definitions for amperage that I've seen before include "current measure" , "Strength of current" .)