Loved this film. It is one of my all time favorite John Wayne films. I watched it again yesterday. My favorite quote is from when JW was stopping the hanging near the beginning of the movie. After the Scotsman (played by the great character actor Bernard Fox) and the little boy leave, Big Jake warns the lynch mob: "You follow him, and I will hunt you down and kill you, every mother-son of you." To me, this sets the tone for the rest of the movie. No quarter given to bad guys. So it was not a surprise when the box had newspaper clippings. Plus, you could see it in the Duke's eyes when he first opens the box in front of Maureen O'Hara. Neither was going to pay for the grief the kidnappers had caused.
I hope this post makes sense.