invasion vs protection

invasion

noun
  • A military action consisting of armed forces of one geopolitical entity entering territory controlled by another such entity, generally with the objective of conquering territory or altering the established government. 

  • The breaching of the skin barrier. 

  • The spread of cancer cells, bacteries and such to the organism. 

  • The entry without consent of an individual or group into an area where they are not wanted. 

protection

noun
  • Coverage. 

  • A means of keeping or remaining safe. 

  • The process of keeping (something or someone) safe. 

  • The state of being safe. 

  • An instance of a security token associated with a resource (such as a file). 

  • Restrictions on foreign competitors which limit their ability to compete with domestic producers of goods or services. 

  • A means, such as a condom, of preventing pregnancy or sexually transmitted disease. 

  • Immunity from harm, obtained by illegal payments, as bribery or extortion. 

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