The United Nations has warned that the world is facing its largest humanitarian crisis since the end of the Second World War. Nearly 20 million people are at risk of starvation in Nigeria, Somalia, South Sudan and Yemen. Last month, the U.N. declared a famine in parts of South Sudan. Earlier this week, aid officials said they’re in a race against time to prevent a famine brought on by a U.S.-backed, Saudi-led war and blockade. Almost 19 million people in Yemen, two-thirds of the total population, are in need of assistance, and more than 7 million are facing starvation. For more, we speak with Joel Charny, director of the Norwegian Refugee Council USA.