Learn English – What does “this… thrusting upon” mean

It refers to the transitive use of “thrust” in conjunction with “on” or “upon”. This is a more unusual way to write that particular turn of phrase.

thrust on/upon
to bring (something or someone) forcibly to someone's notice, into someone's company etc.
He thrust $100 on me; She is always thrusting herself on other people; Fame was thrust upon him.
_{Source: Kernerman English Multilingual Dictionary © 2006-2013, definition of “thrust on/upon”, via TFD}

It might go back to a well-known line from Shakespeare:

Some are born great, some achieve greatness, and some have greatness thrust upon them.
_{Shakespeare, Twelfth Night: Act 2, Scene 5}