What seems to have been the main cause of the 1937 recession? whose economic theory appeared to be supported by the recession and the effect of the administration's response to it?

It was said that the main cause of the 1937-38 recession was the decreasing of the money supply because of the doubling of the funding for the Federal reserve and Treasury Department policies. However, it is still a mystery since this reason does not appear to be valid enough to cause an economic downturn during the Great Depression.