I farm outside of the US, so maybe I have misunderstood something, but did the 2014 farm bill not eliminate those subsidies that people used to talk about with respect to corn? As I understand it, since 2014, the system was brought in line with the system we use in my country. There is crop insurance available to corn farmers, where the government pays a portion (65%, if I recall correctly?) of the cost, but that is not limited to corn and not really an incentive to grow corn in particular. I would not be at all surprised if corn takes the largest share of claims simply due to how much of it is grown.

But it would be seen as a "tax" to the corn producers, beef eaters, sugar water drinkers, car owners, and probably a load of other groups who benefit from the artificially cheap price.

Out of that list, the corn producers can get lost. They are not entitled to our subsidy.

Until Iowa is not the first US primary, these corn producers will always have an an advantage in influencing American politics.

Well sure, but there are a lot of lobbying groups relying on the subsidies. Beef, pork, ethanol, corn syrup, international food exporters.

If a congressperson raises the price of the commodity they all rely on, they will piss of a LOT of money, and probably not raise enough next election cycle, and lose their seat.

>A lower subsidy on corn would significantly raise beef prices relative to chicken,

We export roughly 40% of our corn in the US, it wouldn't increase beef prices prices much, it'd reduce exports though.