President Obama is well acquainted with this crisis. During his career in the Senate, he authored the Democratic Republic of Congo Relief, Security and Democracy Promotion Act. The president should appoint a temporary envoy to signal clearly that finding a lasting solution is a priority for his administration. Past models for this approach — sending Sen. John Kerry to Sudan, veteran diplomat Richard Holbrooke to the Balkans or Gen. Colin Powell to Haiti — demonstrate that high-level diplomatic intervention at the right moment can cut through deadly impasse and open the path toward lasting stability. As a major humanitarian and foreign assistance partner in central and east Africa, the United States has significant diplomatic influence with the key players in this conflict. The Obama administration should leverage this influence first and foremost on behalf of an immediate cease-fire.