Earlier quoted context omitted.
It still means that the US could probably rely on domestic production if it was forced to do so. In a war, no other country could leverage their position by threatening to stop food exports to the US. It would surely result in less choice, but wouldn't really hurt the US.
> wouldn't really hurt the US. My expectation is that it would far more expensive, raising food prices and doing significant harm to the economy. Also imagine the massive costs of shifting production and the gap in food availability during the shift. But I agree that the U.S. wouldn't starve.
I think what would harm us more in total isolation would be the lack of more scarce resources (those used in electronics, batteries etc). We have a lot of materials here, but there are others where China and Africa trade are needed.