Sources I have found say it began in the 1920's, which I don't doubt. But when did it actually become the standard? Very hard to find information on this topic.
One of the most interesting things about iodine/iodide is that it prevents the uptake of radioactive iodine-131, which often causes thyroid problems/cancer. This is a unique radioisotope, doesn't exist in nature. Byproduct of nuke testing and power.
And most of the early articles about iodized salt I have been able to find are from post-1945.
Officials at the Hanford Nuclear Site, which was releasing gobs of Iodine-131, recommended iodized salt to surrounding neighborhoods.
If iodized salt was already the standard, why did local newspapers run stories on the benefits of consuming IS?
There's something extremely fishy about the history of iodized salt. Or am I crazy?
What do you mean by "the standard"? There's never been any legal requirement that salt be iodized. Non-iodized salt is and has always been available. According to this: "In 1955, researchers reported that 75.8% of U.S. households used only iodized salt.", by the same source about 70% of the table salt sold in the US today is iodized.
I don't see what's 'fishy' about making an effort to emphasize the benefits of iodized salt in areas where it had additional health benefits due to possible exposure to radioactive iodine.