Good question I think. Norman Borlaug was known for transforming places with food importers into food exporters. And to ask the question again occasionally makes sense. In recent history we are exploring the idea of vertical gardening etc. I was joking to someone once that we should grow watermelons vertically so that the large heavy melons could power a carousel style escalator or water pumping mechanism.
Not all areas are equally good at growing food. That can be because of climate, soil quality, war or simply population density requiring housing and industry.
Maybe it's too malthusian of a view but I think a big issue to contend with is that some people should not be as populated as they are and there's no push against it from either government or the dominant economic systems.
And yes that includes the controversial poor population hotspots of africa that have grown super rapidly beyond multiples of what the land can provide
But also just the same places like arizona with comparatively rich folk growing the urban desert sprawl
Is shipping food there the correct solution? For war, an ostensibly temporary condition, by all means ship the population food. But if an area is already overcrowded beyond what the land can sustain (due to climate, soil quality, or population density) then is it productive to further bolster the population? Seems a human catastrophe in the making, supporting population growth in an area where the land can not supply enough food.
My worldview is based on the cities I've lived in, in which the citizens of that city have the means to purchase the food themselves. Therefore the movement of food into that city is in the economic interest of those supplying the food. Furthermore, that food _is_ grown locally, within half a tank of gas from the city itself.
I should note that the cities I'm familiar with, and thus my worldview, have multiple thousands of independent suppliers bringing food into the cities as profitable businesses, not a single altruistic organisation functioning off donations. Therefore there are much fewer catastrophic points of failure - an event that would prevent food from getting into the city would be a large, wide geographical catastrophe. Not the whimsical changing of political positions or sudden misfortune of donors. And in this worldview, when natural pressures such as population overdensity occur, the feedback loop stabilises at a sustainable level - those for whom food becomes too expensive move to cheaper places. I've done it myself.