We must remember that the referendum is just one part of a long, complicated, and sensitive process and without significant long-term international engagement there is still a risk of it all falling apart.

The referendum on southern independence is a significant milestone in the 2005 Comprehensive Peace Agreement (CPA) between the Northern dominated National Congress Party and the southern led Sudan People’s Liberation Movement. The CPA brought a formal end to a devastating 22-year civil war that killed more than two million people and drove more than four million from their homes. The United States put a lot of effort into ensuring the referendum occurred on time and peacefully. Amazingly, the weeklong independence referendum, which ended on Jan. 15, was completed without violence or other any significant disruptions. The fact that the vote did not spur any major violence is no small feat in a country where the majority of people have spent most, if not all, of their lives living in a situation of armed conflict.

The January referendum marked the beginning of a new chapter in the history of eastern and northern Africa. After many of these types of global events top policymakers who worked so hard to reach a particular milestone are either tired and leave their posts or take a few months to pat each other on the back and attend ceremonies honoring one another.

However we must remember that the referendum is just one part of a long, complicated, and sensitive process and without significant long-term international engagement there is still a risk of it all falling apart.

If, as the preliminary results of the referendum suggest, southern Sudan voted for succession, this will create not one, but two new countries. The Republic of Sudan will be a very different political entity if the south forms its own country. Both countries will require sustained international support to manage their relationship with each other and other neighbors in the region. There remain several extremely sensitive issues that need to be resolved before the end of the CPA interim period in July 2011, including negotiations oil-wealth sharing, border demarcation, division of debt and questions of citizenship. At the same time the US government and other countries cannot and must not ignore the internal challenges both states will continue to face: the immediate need to protect civilians from violence and provide unimpeded humanitarian assistance, and the long term challenge of providing equitable and sustainable development opportunities and access to basic services.

Over the coming weeks I will use this blog to review some of the key steps the administration must take in both northern and southern Sudan.

The State Department officials who worked so hard to make this referendum happen on time and peacefully deserve a week off. But President Obama and Secretary Clinton need to make sure that it is only a week because the next part will be even harder.