armed struggle vs warfare

armed struggle

noun
  • An irregular political conflict waged by an armed rebel group attempting to overthrow the prevailing regime or otherwise win political rights. 

warfare

noun
  • Military operations of some particular kind e.g. guerrilla warfare. 

  • The waging of war or armed conflict against an enemy. 

verb
  • To lead a military life; to carry on continual wars. 

How often have the words armed struggle and warfare occurred in a corpus of books? (source: Google Ngram Viewer )