animosity vs tug of war

animosity

noun
  • Violent hatred leading to active opposition; active enmity; energetic dislike. 

tug of war

noun
  • A dispute between two parties, particularly an entrenched, back-and-forth dispute. 

  • A game or competition in which two teams pull or tug on opposite ends of a rope trying to force the other team over the line which initially marked the middle between the two teams. 

How often have the words animosity and tug of war occurred in a corpus of books? (source: Google Ngram Viewer )