It's one of the great ironies of our age – learning that millions are being lifted out of desperate poverty at the same time as millions more are falling into famine. Thanks to system change many of what are termed the “bottom billion” are finding their lives slightly improved. Yet it is also because of the lack of human intervention – the worst possible kind – that hunger has huge populations on the brink of starvation. The UN's Sustainable Development Goals (SDGs) are offering some hope through a vast collaborative global effort. At the same time, regional conflict, corruption, mismanagement and apathy are thrusting millions in the vortex of extinction.When the United Nations recently announced that some 20 million people in four countries face famine it supported that reality with a staggering claim: this summer is witnessing “the worst humanitarian crisis since the end of World War Two.” China lost 30 million people to starvation following that great conflict, while much of Europe faced its own struggles with famine. How can it be that just four famine stricken nations – South Sudan, Nigeria, Yemen and Somalia – can face even worse disaster than a half-century ago?According to the study, Tufts Famine Trends, modern famine emerges because those amenities that have reduced hunger in recent decades – improvements in farming, transportation and communications infrastructure – are severely missing in the four nations mentioned above.This is the great tragedy in what these millions now face: it isn't because of a lack of food only, but because human design has determined that it will leave hunger untreated until it reaches epidemic proportions, better known as famine. Who are we talking about here? Undoubtedly the governments of those regions haven't been able to get their acts together, sometimes through corruption, tribalism or willful neglect. But another key component is us – prosperous and developed nations. When resources have been lacking to build the roads, buy the seeds, transport the yields and get them to markets, the UN has put out special appeals over the past few years, warning that if donor countries failed to respond that the inevitable results would be famine in these regions. The response has been so dismal by governments and their citizens that the food crisis prophesied has now come to pass.Chris Hillbruner of the Famine Early Warning Systems Networks recently said plainly, “When the political will is there, everyone suddenly has access.” We know this to be true – it always has been – but the opposite has direct consequences: low political initiative leads to disaster. As UTNE Reader put it: “The Rich Get Richer; the Poor Go Hungry.”The distinction between hunger and famine is vital for us to consider and understand. Almost one billion people in this world live in chronic hunger yet have enough to survive. They will experience poor health, disease, and high child mortality, but they can likely endure. Famine is different. People in such a condition don't have enough food to survive and will soon enough perish, starting with the most vulnerable. Hunger is about surviving; famine is about death. That's the distinction. The key is to keep people migrating from the former to the latter.The cause of famine carries with it much more human design than we might care to admit. Yes, there are the civil wars, corruption and other domestic failures that keep people from getting the nourishment they require to live. But then there are those individuals, groups and nations that refuse to provide the required resources to keep families falling from hunger into famine. These two dimensions, regional and global, when combined, lead to the crisis that the UN is now alerting us to.One of the great tragedies of famine, as Oxfam continues to remind us, is that if we wait until famine is declared to respond, it is too late. That's the reason the UN provides advance warnings. But what happens if the response isn't sufficient? We are now about to find out.Our family has worked in South Sudan for 18 years and at no time has it been easy. Yet our women's initiatives and education programs have progressed even during times of great civil war. But this past January, with no fighting occurring in the Aweil East region where we work, the threat of famine entered the area and everyone knew what it meant. What war, tribal divisions, hunger, lack of medical services, the recruiting of child soldiers (including girls), too many deaths in childbirth, and lack of rain couldn't accomplish, famine can now succeed through the perishing of these remarkable survivors themselves. It is enough to induce heartbreak, as it has done many times.This is what constitutes the ultimate tragedy wrought by famine – it destroys hope by obliterating the people themselves. Eventually deaths of such magnitude will dislocate much of world unless the nations and peoples of the world respond. This isn't a question of merit but of life and death. The call for assistance went out two years ago. We can now only pray for two things: enough time to respond and enough of the world to intervene and keep not just hope alive, but the very people themselves.Glen Pearson was a career professional firefighter and is a former Member of Parliament from southwestern Ontario.  He and his wife adopted three children from South Sudan and reside in London, Ontario.  He has been the co-director of the London Food Bank for 29 years.  He writes regularly for the London Free Press and also shares his views on a blog entitled “The Parallel Parliament“.   Follow him on twitter @GlenPearson.