Sentence:  Historians such as Liah Greenfield and Daniel Chirot have attributed the major wars and genocides in the early decades of the 20th century to <WSD>ressentiment</WSD> in Germany and Russia. 
Meaning of the word marked with <WSD> tags:  A sense of resentment arising from suppressed feelings of envy and hatred, often leading to a frustrated sense of inferiority, with various social repercussions. (from 19th c.)