Here are the facts:
Trade only amounted to 6% of GNP to begin with, and it declined to 2% of GNP by 1932. Furthermore, since Smoot-Hawley only applied to 1/3 of imports, you can't even attribute the 4% drop to the tariff. Rather it was the 31% decline in GNP and 25% unemployment rate that more drasticly reduced demand for imports.
A Google search reveals sufficient background information on the two relatively unknown wannabes you cite. However, the mere fact that you reference them in support of your absurd contentions is enough to condemn their credibility. They eschew valid academic methodology by assuming the politically correct result they desire is "true", then manipulating historical data and facts to support their incompetent assertions.
Senator John Heinz III, who died tragically in a plane crash in 1991, had developed a national reputation for his expertise in international commerce. During his years of serving in Congress, Senator Heinz III was appointed to the Chairmanship of the Subcommittee on International Finance and Monetary Policies. He had this to say about the Smoot-Hawley myth in 1985:
“It gravely concerns me that every time someone in this administration or the Congress gives a speech about a more aggressive trade policy, or the need to confront our trading partners with their subsidies, barriers to imports and other unfair practices, others in Congress immediately react with speeches on the return of the Smoot-Hawley Tariff Act of 1930, and the dark days of blatant protectionism and depression...It seems that for many of us that Smoot-Hawley has become a code word for protectionism and, in turn, a code word for the depression. Yet, when one recalls that Smoot-Hawley was not enacted until more than 8 months after the October, 1929 collapse, it is hard to conceive how it could have led to the Great Depression...the changes supposedly wrought by this single bill in 1930 appear fantastic.”
BTW, the late Senator Heinz entered Harvard Business School in 1961, and the following year worked for the summer with the Union Bank of Switzerland in Geneva. He received his Master's degree in Business Administration from Harvard in 1963. That's sufficient academic background for competent understanding of economics to be authoritive on the subject, unlike your voodoo propagandist Wanniski.
Amazing that you would cite Heinz, whose Harvard degree is no better than Bush's, but disregard established economists who have actually done research in the field. And NO, you can't get what you "need to know" from a "google" search. That is purely moronic.
And no, it doesn't matter WHEN the final vote was, the Hawley Smoot deal was "done" the day before the crash. Obviously you have memory loss, or you would know that the CLINTON impeachment was "done" the day it was voted out of the judiciary, because you don't vote those things OUT unless they are going to pass. Likewise, the impeachment was DEAD the minute the Senate adopted its "rules." But guess what? The final "vote" wasn't for weeks.
But hey, live in your dream world. There aren't a handful of economists alive today who don't think that HS was a MAJOR contributor to the Great Depression, but even without it, your stupid argument is childish: every piece of evidence we have shows that FDR's abominable New Deal policies EXTENDED and DEEPENED the Depression. There is plenty of research on Glass Steagall (terrible); Minimum Wage Laws (drove millions out of work, right in the pit of the depression); FDR's hideous tax laws that ensured there would be no recovery; his pathetic spending programs, building opera houses when Americans couldn't even afford to go to movies.
The Dems and FDR in particular engaged in a war against the middle class and the poor, and framed it in rhetoric of hatred of the rich. But Hawley Smoot and the Fed started it all, so I can't blame him for that. (Notice, by the way, the EUROPEANS' response to HS was to enact barriers, so no more overseas trade.)