So much for the myth that Smoot-Hawley and Hoover's "protectionism" was what caused the Great Depression.
The Fordney-McCumber Tariff of 1922 wasn’t much different than Smoot-Hawley, 1930.
Those who wish to attribute the Great Depression to Smoot-Hawley need to explain why Fordney-McCumber was followed by the Roaring 20s rather than a depression.
The cause of the Great Depression was the collapse of the American banking system over the years 1930-33. One third of American banks failed and one third of the American money supply simply vanished as fractional reserve banking went into reverse.
This is all covered in Milton Friedman and Anna Schwartz “The Great Contraction”. The banking collapse was due to series of blunders by the Federal Reserve combined with the absence of FDIC, Federal Deposit Insurance.
http://papers.nber.org/books/frie65-1