I was watching this old Movie on TCM, Gold Diggers of 1933. At the end, Joan Blondell starts to speak sing this song. The clip I found from the movie was a little long so I found this updated version which shows how everything seems to remain the same.
The movie made a statement about those WWI Vets who went to Washington to ask for their promised Bonus for serving the Country during WWI. The Bonus was to be paid after twenty years but so many were rendered destitute after the 1929 crash that they were there to petition the government for early payment. The government in the guise of MacArthur, attacked the Vets and physically removed them from the Capital.