Building sustainable peace is a central challenge of our time. Where wars have been fought in the past century, 100 million civilians died.

Today’s 25 conflicts are producing familiar consequences: refugees, destabilized neighborhoods, pandemic disease, starvation and enormous economic dislocation. The international repercussions of poor governance, weakened rule of law and economic stagnation include the spread of weapons of mass destruction and terror.

To alleviate the disruption and devastation that people suffer, the United States and its global partners must increase and improve our post-conflict reconstruction capacity. This will be an immense challenge, made more difficult by the resistance to change of existing architecture and institutions, bureaucratic infighting and inertia.

We have seen small problems in small places, small problems in large places, and then large problems in small places. From Somalia to Haiti, Bosnia, Kosovo, Rwanda, East Timor, Guatemala, Afghanistan and Iraq, our efforts have been mediocre. In each case, anticipation was poor, leadership was ambiguous and multilateral energies and national resources were consumed.

History’s flow, and the experiences of the past two years, suggests that we will face ever-greater challenges. Now, with little preparation to deal with even the most modest challenges, we are rapidly moving toward reconstructing larger countries, with expansive landscapes and sprawling populations. Yesterday’s Timor is today’s Iraq, 25 times larger in every way.

As our existing institutions and structures struggle with the new reality it is clear that we are not even ready for yesterday’s disasters, much less today’s chaos, or tomorrow’s cessation of fighting. Sudan is a good case.

The largest country in Africa, with the longest war, Sudan, spans the Arab and African world within its 2.5- million square kilometers and its 38 million people. Wracked by nearly 40 years of fighting between the government and the Southern Peoples Liberation Movement/Army (SPLM/A), the conflict has taken the lives of some two million Sudanese since 1983 alone, and displaced five million more.

Yet, peace is possible. Warring parties are nearing agreement and a suffering populace eagerly awaits a peace dividend.

Even with an accord the celebration may be short-lived. For once the ink dries, the true test begins.

Most of the burden will fall on the Sudanese themselves, but important outside guarantors will be needed. Countries like the United States, Britain, Norway and Kenya have already contributed huge amounts of humanitarian aid (the U.S. alone has contributed close to $2 billion since 1983), and less significant economic and human capital. These efforts will need to be renewed and expanded.

As usual, ensuring security should be the top priority for the international community. In the immediate aftermath of a peace deal, rule of law and governance will be understandably weak. This power vacuum will tempt rebel leaders, government officials, militias and other strongmen to enter into a competition for supremacy. Without police, human rights monitors and peacekeeping forces Sudan’s hope for democratic governance and a sustainable peace will remain a distant dream.

An international quick response force could serve as a crucial first step in restoring personal safety to the Sudanese. The credible deterrent and enforcement value of a rapidly deployable unit will be a catalyst for future reconstruction endeavors, including: justice and reconciliation, governance and participation, and economic and social well-being.

For Sudan, chronic fighting has led some to a culture of violence. To convince the population that their rights will be protected and their grievances addressed without the need to seek revenge, will require a robust public safety and judicial sector, cultivated, initially, by international players.

Long-term growth will depend on burden sharing with the Sudanese and an expansion of external assistance. Entrepreneurial models, such as the Joint Military/Monitoring Commission, which addresses security matters using international support, sidesteps the legacy of mistrust while integrating local representatives to guarantee indigenous ownership, and serves as a model for future strategic ventures.

Each new post-conflict challenge brings hope that the international community will begin a reformation process that will evolve into a functioning institutional capacity for rehabilitating war-torn societies. Resting just over the horizon, Sudan provides an opportunity to begin thinking now about how to improve our reconstruction efforts, and could serve as the catalyst for a movement that takes us from mediocrity to excellence.

A more peaceful world will depend on our ability to deliver in the aftermath of warfare.

Rick Barton, former Deputy High Commissioner for Refugees at the United Nations, is a senior adviser at the Center for Strategic and International Studies in Washington, where Doug Henry is an associate on post conflict issues.