As you mentioned, it's all about balance. Despite our best intentions, we need to be realistic about what we can do in every region and what the most effective way is to provide those populations with the food they need.
In some places, the challenges can revolve around geography, a lack of farmland and drought. No matter how hard we try, those places will always have a limited capacity to produce certain foods, at least. That is why it's important to look at the situation when determining what is feasible and to pay attention to regions in the world with overproduction.
Science can still play a role in helping to build local production capacity, such as the identification of seed varieties that are drought-resistant or better able to withstand diseases common in certain regions.
It's a complex issue, and it requires proper analysis. It all comes down to one question: What is the most effective and efficient way of achieving the goal?