Wiktionary
little eichmanns
n. (little Eichmann English)
Wikipedia
Little Eichmanns
"Little Eichmanns" are persons participating in society whose actions, while on an individual scale may seem relatively harmless even to themselves, taken collectively create destructive and immoral systems in which they are actually complicit.
The phrase gets its name from Adolf Eichmann, a Nazi bureaucrat who unfeelingly helped to orchestrate the Holocaust.