As the first ever U.S.-Africa summit opens in Washington today, all is not quiet on Congo’s eastern front. Just before the 4th of July when most Americans were watching fireworks, diplomatic pyrotechnics erupted in Africa that now seriously threaten to reignite the war in eastern Congo, a conflict that has left more people dead than any war since World War II. The kerfuffle concerns the rebel group that has been at the center of the war, the Democratic Forces for the Liberation of Rwanda (FDLR), a dangerous militia based in Congo and led by some of the perpetrators of the 1994 Rwandan genocide.

Because it is at the heart of the war, ending the FDLR must be a centerpiece of the peace process. Over the past 20 years, neighboring Rwanda has invaded Congo twice and sponsored three major rebellions in eastern Congo—all in the name of countering the FDLR and its predecessors. The war escalated significantly in 1994 when the first iteration of the FDLR, the Interahamwe and members of the former Rwandan army, crossed into Congo from Rwanda after the genocide, and tens of thousands of people died when Rwanda pursued the group in Congo. The FDLR represents a unique threat to Rwanda because its leaders espoused the elimination of Tutsis from Rwanda, the twisted ideology at the heart of the mass killings there. Only people who have gone through genocide can fully comprehend such an existential threat.

Since then, the partially Rwandan war being fought on Congolese soil has inspired the creation of dozens of Congolese armed groups. These militias have wrought tremendous havoc on local communities, with the FDLR intensifying the horrific tactic of rape as a weapon of war. Today, over 30 armed groups remain in eastern Congo, many of which were created or supported by the Congolese or Rwandan governments in their battle for the region.

A few months ago, after years of hand-wringing, the international community was finally preparing to support military operations against the FDLR. But the Congolese government, which is 154th out of 175 countries on the world corruption index and which continues to collaborate with the FDLR, according to the United Nations, successfully pushed the region and the UN to accept a plan that delays military action against the FDLR to give it a chance to voluntarily disarm. South Africa and Tanzania, who are allied with Congo President Joseph Kabila and have their own, separate disputes with Rwanda, managed to secure for the FDLR a six-month respite from any forcible disarmament operations by the UN. They succeeded despite efforts by the global body, the U.S. and Angola, who don’t think the FDLR will voluntarily disarm.

The major risk here is that if the FDLR regroups, it provides a rationale for Rwanda to remain militarily engaged—directly or through proxies—in eastern Congo. The UN highlighted recently that the FDLR is actively recruiting troops, including children, and building alliances with three Rwandan political parties in a bid to unseat President Paul Kagame in the 2017 elections. If Rwanda does cross the border in response, it would significantly escalate the war and humanitarian crisis.

President Obama’s U.S.-Africa Summit, starting today, offers a critical opportunity to help prevent that worst-case scenario. The President, Secretary of State John Kerry, National Security Adviser Susan Rice, Ambassador to the UN Samantha Power, and Special Envoy Feingold should engage the presidents of the key countries involved—Congo’s Joseph Kabila and South Africa’s Jacob Zuma—and make it clear they must take serious action on the FDLR over the next six months, and that the U.S. stands ready to support such actions.

Three steps are needed to avert a new crisis. First, the U.S. should press Congo to suspend and prosecute its army officers involved in collaborating with the FDLR. The Congo-FDLR links are documented year after year in UN reports, and yet not a single suspension or trial has ever occurred. Second, Congo and the region must agree on three-month benchmarks for FDLR disarmament that include the demobilization of at least half of the FDLR’s senior leadership, not simply rank-and-file militia. Third, the U.S. should offer Special Forces military assistance to the UN’s special unit, the Intervention Brigade, in fighting the FDLR. U.S. Special Forces advisors and aid have been a major factor in reducing the strength of a similar nearby militia, Joseph Kony’s Lord’s Resistance Army (LRA). Washington should build on successful tactics against the LRA and work with the UN to apply those to the FDLR.

Congo’s wars over the last two decades have cost over five million lives. The lasting effects of the Rwandan genocide have been at the root of these conflicts. Until this core driver of violence is eradicated, turbulence is guaranteed in Congo’s east.

Ending the FDLR with focused military operations, targeted prosecutions, and a well-conceived disarmament and demobilization strategy would be a huge step towards laying the foundation for peace in Congo and across the war-scarred region of central Africa.

John Prendergast is the Founding Director of the Enough Project.

Sasha Lezhnev is Associate Director and Senior Policy Analyst at the Enough Project, where he focuses on peace and conflict minerals in the Democratic Republic of Congo.