The Original Miracle of 34th Street is my all time favorite Christmas Movie—there are others that are humorous like A Christmas Story or even Christmas Vacation, but Miracle is the best IMHO. Beats that Jimmy Stewart Slush factory by far...
During filming, James Stewart was actively suffering from PTSD and depression due to his service in World War II. Stewart told friends that he related a lot to the character of George Bailey, some of the scenes where George acted out in anger was considered “cathartic” for Stewart and his struggles with mental health. Stewart’s acting became notably darker after the war as he knew he had killed civilians in Germany and occupied Europe. https://www.imdb.com/title/tt0038650/trivia/?ref_=tt_dyk_trv