please help with American Economic History topic. Conduct original research on an American Economic

please help with American Economic History topic.
Conduct original research on an American Economic History event that occurred between 1900 – 1960. (you cannot do the Great Depression or Prohibition) . I chose The Great Mississippi Flood of 1927, but my professor said ” Your topic on the Mississippi Flood of 1927 causing state revenue to decline is fine but isn’t that great of topic. I don’t think anyone in the class would argue that a flood causes devastation which lowers the intake of taxes. I really want topics where we don’t know the outcome.”
Please help to give me some topics