JUBA, South Sudan — Less than a week after the United States celebrated its Independence Day for the 235th time, another nation was born, beginning its journey into history. That would be the Republic of South Sudan which raised its flag for the first time as a sovereign state in ceremonies in its capital Juba on Saturday.It was my privilege to be here as part of the official U.S. delegation which was led by United Nations Ambassador Susan Rice. My inclusion in that delegation is in part recognition of the work that my group, Catholic Relief Services, has done in South Sudan in the years of struggle and hope that led to this moment. But mainly it is a recognition of the efforts of so many American humanitarian organizations, of volunteers, of dedicated professionals, of clergy and lay people, of all sorts of caring groups and individuals whose efforts helped make this day possible.Certainly this is a time of celebration. The gestation of South Sudan included decades of war that left millions dead and displaced. It included peace building work – often led by churches – at every level, from resolving small community disputes to involving the largest international actors.A 2005 peace agreement led to a referendum on secession held in January. Go back a couple of years and you could find few people who thought that vote would come off peacefully given the powerful legacy of violence. But the people of South Sudan, supported by their friends around the world, surprised us.And so we came together on Saturday for a celebration that was well deserved. South Sudan created a small miracle.But we have to inject a sobering reality into a time of joy. The hard part of South Sudan’s journey is not over, it is just beginning. What those of us who care about this country must not do is see independence as the happy ending to a play, applaud as we watch the curtain close, and move on. We must not do that because South Sudan will need us in the years and decades to come.For one, violence has not disappeared. Most alarming has been fighting in the border areas in the run up to South Sudan’s independence day. The world diplomatic community must put its full efforts into resolving these disputes in a peaceful manner that respects the rights of all.Beyond that, while the South Sudanese have achieved their independence, they are still desperately poor. The area that makes up their new nation has been long neglected, dating back to the era of British colonial rule. Fighting over its status began soon after the British left in 1956 and continued for most of the next 40 years. Those decades of war left devastation behind. By every measure – health care, roads, agriculture, education, water and sanitation, civic institutions – South Sudan is a country with immense needs.It certainly has resources – oil, fertile land – that will help it on its journey. Most importantly, it has resilient and resourceful people who are clearly willing to sacrifice for the good of their country. But if South Sudan is to succeed, all of us who worked so hard in the past years to try to bring peace to the area must stay with it, redoubling our efforts to support this fledgling nation.History teaches that we must not neglect countries in their times of transition – Afghanistan, Eritrea, East Timor. The lesson is clear – we need to stay with these countries after the firing stops, after the votes are cast, after the new flag is raised.And so we must stay with South Sudan, all of us – humanitarian groups; the governments of the United States, of China, of Europe, of Sudan’s neighbors on the African continent; international agencies like the United Nations; and all the people around the world who celebrate this new country.A new nation has been born. Let us all be the village that helps raise it into a healthy and prosperous adult that takes its rightful place in the world.