Corn lobby's war on sugar cane in USA is well known. Sugar cane lobby is much smaller but successful nonetheless.
This corn stuff is ridiculous, it's soviet tier, you produce tons of it and only latter you worry about how to spend it, and this is why corn lobby is go gigantic. And this shit is now also spreading to Brazil. Same arguments, they argue that nothing beats corn when you look at productivity numbers, it's very resistant to both drought and rain, absorbs lots of sunlight, produces lots of callories per hectare, etc, and this is why we should plant more corn, but conveniently ignore that we do not consume this much corn in our daily lives unless it's highly processed. So they lobby the shit out of everybody to push their corn shit down everybody's throat.
Corn here is also threatening ethanol production from sugar cane. Sugar cane is far more productive and green when it comes to ethanol, but corn is cheaper, because it can be easily stored to be processed all year round. Sugar cane has to be processed in a max of 48h after it has been harvested. When your corn lobby lobbied the Bush administration to subsidize corn ethanol, they lied, claiming that they could turn cellulose into ethanol too. Breaking cellulose isn't rocket science, but doing it in an economically feasible scale has always been a challenge. Everybody knew that corn was nowhere near as green as sugar cane, everybody knew that the celulose thing was bullshit, and in any case, cellulose exists in all plants, sugar cane cellulose could also be turned into ethanol if such technology became available. But your corn lobby kept lying, they said that they could do it, but never delivered. When americans finally became disillusioned with corn ethanol, realizing that it was never going to be green, your corn lobby quietly released a statement admitting that the whole cellulose thing was never achievable, but that they needed subsidies anyway, as well as laws forcing your refineries to mix corn ethanol with gasoline (because otherwise refineries wouldn't do it), because "it's still our better option for green fuel". Which once more is a lie, you could greatly expand sugar cane plantations in florida and other parts of your south, plus Puerto Rico, but your corn lobby has successfully lobbied against your sugar cane for decades. And because our farmers couldn't compete with your corn ethanol, they begun to switch from sugar cane to corn too. But more importantly, in the end, because americans didn't believe in biofuel anymore, thanks to your corn ethanol, they begun to look forward to electric cars as the new green tech. Basically, your corn lobby is responsible for Elon Musk.
All of this shit because your greedy corn farmers keep trying to push their over-production down everybody's throat (and our farmers are now also doing the same thing here). Corn farming is a plague on Earth.