Complex sentence: This deep hostility towards and fear of Communism would be the more lasting legacy of Kun's abortive revolution: a conviction shared by Horthy and his country's ruling class that would help drive Hungary into what might have been a fatal alliance with Adolf Hitler.
Split into simpler sentences: This deep hostility toward Communism would be the more lasting legacy of Kun's abortive revolution. It was a conviction shared by Horthy and his country's ruling class that would help drive Hungary into what might have been a fatal alliance with Adolf Hitler.