The coronavirus pandemic has laid many things bare, none more so than how interconnected our world is. The impact of globalization is most obvious in the stuttering supply chains that threaten food security worldwide. Maintaining or reweaving these webs is going to take technology, innovation and political determination. As chief economist at the Food and Agriculture Organization of the United Nations (FAO), I fear that few countries have recognized that their measures to contain the virus and buffer economic shocks must be adjusted to keep food flowing. Without food, there can be no health. The policy prescriptions are straightforward, and isolationism can form no part of it. Countries must work together, not throw up trade walls and bar essential workers from crossing borders.