Originally a British communist who supported Khrushchev sending the Soviet military, which included tanks, to aid the Hungarian People’s Republic against the uprising in 1956, as named by those who disagreed with it. It took off online a while ago and now means something different to everyone who says it, anywhere from strictly Marxism-Leninism to anyone with politics further left that appointing Trump emperor of Earth. We’re usually being at least one kind of sarcastic when we use it.