“If you had a billion dollars to spend, how could you best help the world?” It is a question I hear a lot, and with the intensification of the conflict in Ukraine, it has only become more urgent. There is a philosophical movement, Effective Altruism, devoted to this issue, but mostly the debate about charity has been set in a world with a relatively stable geopolitical order. How should war change the answers?

I don’t know how best to help the immediate victims in Ukraine, but I have some ideas about how the conflict should change broader philanthropic priorities. In times of war, it is all the more important to focus altruistic efforts on two issues: food and migration.

During wartime, basic human needs become more pressing, most of all food. For instance, Ukraine supplies much of the world’s grain, including to many of the world’s poorer countries. The largest importers of Ukrainian grain are Egypt, Turkey, Bangladesh, Indonesia and Pakistan, and in percentage terms Yemen, Libya and Lebanon are especially dependent. To the extent the conflict and sanctions disrupt Russia as well, Russia is not only a major grain exporter but also the largest exporter of fertilizer.

With so much of Ukraine under siege, these supplies are a mix of blockaded or endangered, thereby creating hunger and malnutrition risk for grain importers.

Increasing the productivity of agriculture, especially in poorer countries, now should be a higher priority. When food supply from one source such as Ukraine is shut off, poorer nations should have other supply options. The Green Revolution has been wonderful for India and Pakistan by increasing crop yields — but it turns out much more agricultural innovation is necessary.

One danger is that a more conflict-prone world will become more protectionist and restrictionist, to ensure the availability of domestic supplies, whether of food or other commodities. That would make it harder for the poorest and most victimized societies to find alternate supply sources when faced with crises. The goal should be a world of food plenty and relatively free trade, not national self-sufficiency.

The important point is how the relative calculus changes in times of major conflict.

In a world at peace, public health interventions yield high returns, and they probably still will in wartime. But their relative benefits, compared to other interventions, may diminish. Saving lives with medicine is worthwhile, but many medicines are expensive. If lives can be saved by the mere shipment and trade of food, and at a profit at that, that will be preferred over saving lives with medicine.

The transfer of public health services also may be less damaged by wartime conditions. Often the public health remedies come from the U.S., Western Europe, or a small number of other relatively wealthy countries. Those countries are less likely to be affected by major wars. So if a major war does come along, the flow of such public health remedies probably requires less repair work than does the flow of food. Unlike advanced medicines, foodstuffs are very frequently traded from one poor or middle-income country to another.

Another philanthropic priority in wartime is the discovery and reallocation of talent. Before, during and after World War II, for instance, a significant portion of Europe’s cultural and scientific talent moved to the U.S. or other Anglo countries. Both the U.S. and the global scientific community were much better off as a result.

It is thus all the more imperative that talented people leaving Russia, Ukraine and Belarus have good options. Not only could their talents be squandered if they stay, but their productivity could be improved if they leave. Russia, Ukraine and Belarus have reasonable education systems and long histories of producing gifted artists and scientists.

How good is the infrastructure for getting people out of Russia, Ukraine and Belarus? How readily can the refugees be matched to where they ought to go? Is there supportive infrastructure along the way? What about the Russians who are outside of Russia’s border and don’t want to go back — what kind of legal status might they hope to achieve?

Heroic efforts are being made to help the Ukrainian refugees, but much of it is improvised. The world can do much better, including for citizens of Russia and Belarus, and I hope we will.

Bloomberg Opinion columnist Tyler Cowen is a professor of economics at George Mason University. This column does not necessarily reflect the opinion of the editorial board or Bloomberg LP and its owners.