The core data for the argument:
“in most years that Smoot-Hawley was in effect (1930-1945)”
takes into account huge productivity increases caused by WWII, which it is generally agreed helped solve the Depression. This is data cherry picking, something for which people in my industry are quickly chastized and earn a black mark.
I know of nobody who argues that Smoot Hawley CAUSED the Depression, so the author is attacking a staw man that does not exist. Economists argue that Smoot Hawley EXTENDED the Depression, which when the Depression continued for an additional decade after Smoot Hawley (rather than self-correcting withing 18-24 months) indicts Smoot Hawley by coincidence at least.
There really wasn’t the increase in war production until 1942...the US did not enter the war until late 1941 after Pearl Harbor...and heavy production kicked in around 1943.
I did originally consider omitting the war years....but then I thought I would get much more criticsm for not including them. I did note that wartime affected trade