The Wire: appropriate to include US city blokes (8)
I believe the answer is:
filament
'the wire' is the definition.
(filament is a kind of wire)
'appropriate to include us city blokes' is the wordplay.
'appropriate' becomes 'fit' ('fit' can be similar in meaning to 'appropriate').
'to include' means one lot of letters goes inside another.
'us city' becomes 'la'.
'blokes' becomes 'men' (I've seen this in other clues).
'la'+'men'='lamen'
'fit' going around 'lamen' is 'FILAMENT'.
(Other definitions for filament that I've seen before include "'Thin wire, in a bulb say (8)'" , "It glows in a light bulb" , "Fine thread" , "Slender fibre or wire" , "Strand" .)