firing line vs métier

firing line

noun
  • The vanguard of an activity. 

  • A situation in which someone or something is targeted. 

  • A row of shooters. 

  • The line from which soldiers fire their weapons at a target; especially the front line of troops in a battle. 

métier

noun
  • An activity to which a person is particularly suited. 

  • Any activity that is pursued as a trade or profession; a calling. 

  • An outstanding or beneficial feature. 

How often have the words firing line and métier occurred in a corpus of books? (source: Google Ngram Viewer )