I came and did bad thing for poor US people (8)

I believe the answer is:

medicaid

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'thing for poor us people' is the definition.
I can't judge whether this defines the answer.

'i came and did bad' is the wordplay.
'and' says to put letters next to each other.
'bad' indicates anagramming the letters.
'i'+'came'+'did'='icamedid'
'icamedid' anagrammed gives 'MEDICAID'.

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I've seen this clue in The Times and The Sunday Times.

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