In political jargon, a useful idiot is a person perceived as a propagandist for a cause whose goals of which they are not fully aware, and who is used cynically by the leaders of the cause.
Wikipedia
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it started with leftists in the West sympathizing with Communists
and Lenin calling them his "useful idiots"
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in every generation leftists in the West end up as someone's useful idiots
today
terrorists
dictators
for whom they have much sympathy against the West