I think it is important to point out that the article is the product of a libertarian political think tank. I have also cited to FEE, occasionally (usually to avoid complaints about biased sources), so there is some merit to their analyses - in addition to bias. In this case, that bias is apparent. It is a broad consensus of economists that Smoot-Hawley was bad policy and very badly timed. But it was not the cause of the depression. Bank policies didn't help, but again, were not the cause of the depression. It wasn't government intervention at all, but speculation and cyclical business realities. Greed and corruption, mostly.