Should they grow vegetables and corn to eat or should they grow corn to feed cattle so they can eat beef?

It should be both. But instead of feeding cattle corn-grain, the corn plants should be (and are!) fed to cattle. However the US has had to deal with an excess of corn, so to make use of all that corn that is grown every year, it is fed to livestock. So in other Words, there's not enough people around to eat all that corn that is grown. And few countries from other parts of the globe will take the State's excess of grain because of foreign policies and trade restrictions. So we're kind of stuck in a rut here. However food scientists have been breaking down, manipulating and processing corn to be put into almost all different types of foodstuffs we eat today.

Cattle are not meant to eat such high concentrated foods like corn and other vegetables, because they are an unnatural diet for them. But that doesn't mean they can't efficeintly convert them into beef, because cattle are able to use plant products far more efficiently than humans can; we'd eventually starve to death on a plant-only diet. However, I do believe that vegetables and corn should be grown for human consumption, but the parts of the plants that we don't eat should be allowed to be fed to livestock. Plus, beef should come from animals that have been on pasture or fed a diet with more roughage, not on a high-concentrate grain-only diet.

But the above can only be dreamed of in a world where imbalance is commonly found. If the USA didn't grow so much corn, and instead put those fields of corn into, say, pasture for livestock instead, as well as reducing the numbers in feedlots, plus do a mandatory approach to increase more healthy balanced diets of more vegetables and less meat (but not taking meat out entirely, as it is an important part of our diet for iron, B-vitamins, calcium, omega fatty acids and many important amino acids that are not found in plant-based proteins), then things would definitely balance out better.