At the start of Russia's war on Ukraine, Moscow's naval blockade threatened the food supply for an estimated 70 million people. A deal was ultimately reached that kept agricultural shipments moving through the Black Sea. But now that deal has broken down, and even commercial ships are increasingly under attack. Martin Griffiths, the former UN Under-Secretary-General for Humanitarian Affairs and Emergency Relief Coordinator, led the task force that helped broker the last grain deal. He joins the show to discuss. Also on today's show: Singer/songwriter Paul Simon (from the archive); Atlantic staff writer Michael Powell  Learn more about your ad choices. Visit podcastchoices.com/adchoices