The official start of the Great Depression is Sept. 1929. The Smoot-Hawley Act was signed June 1930 10 months AFTER the start of the Great Depression.
The Official Start is not the real start. The economy was sliding and businesses and banks were pulling back during the time that Smoot Hawley was being processed in Congress which began well before the Crash. When it became obvious that it would pass, the market crashed. I wish folks would read some Economics instead of magazine articles and party platforms.