> Couldn't other countries step up production or tap into their grain reserves? Stepping up production isn't easy, since most arable land is being used for foo

> Couldn't other countries step up production or tap into their grain reserves? Stepping up production isn't easy, since most arable land is being used for food production already. You'd have to increase farming efficiency. (Which is possible, but not easy; nobody wants to do inefficient farming, so if, as a farmer, you haven't raised efficiency, it's likely that you don't know how, or simply cannot, due to other constraints, such as availability of machines and fertilizer).