Lenin was imprisoned and then exiled to organize from abroad. Stalin stayed underground and had to organize in secret, narrowly avoided prosecution by the authorities numerous times. These people were living dangerously.
Chinese communists had it even worse. During the Long March, attrition rate was 95%, either died fighting the pursuing KMT forces, or from exposure to the elements. Barely a few thousand cadres made it to Yan’an, outgunned and outnumbered, after trekking thousands of miles of the most arduous mountainous terrain. Without ideological conviction, the group would have disbanded long before they made it to their destination.
Trump can smell weakness and goes straight for the killing blow. This is the kind of people he likes to bully the most.