THE UNANIMITY with which the United Nations Security Council approved a peacekeeping force for the Central African Republic early this month attested to the dire situation in that impoverished country. More than 630,000 people in a nation of 4.5 million have fled their homes, and tens of thousands are living in miserable and dangerous conditions at the airport in Bangui, the capital, or in other improvised camps. Just 6,000 African and 2,000 French troops provide what passes for protection and order in a country where the state has collapsed. The U.N. force, which will consist of 10,000 troops and 2,000 police, is not due to deploy until September.

The first challenge this dismal situation presents is how to protect the refugees until the U.N. force arrives. Most endangered are the country’s Muslims, who became the target of a vicious outbreak of sectarian attacks by members of the Christian majority after a Muslim-led government — itself guilty of mass brutality — collapsed in January. Of the 100,000 Muslims who formerly lived in Bangui, fewer than 1,000 remain, and some 80,000 Muslims have fled to neighboring countries. Unless the tide can be reversed, the destruction of their communities may be irreversible.

To be sure, not only Muslims are at risk. On March 29 Chadian troops killed about 30 people and injured more than 300 at a Christian market in Bangui. Chad, a majority-Muslim country, later agreed to withdraw its 850 peacekeepers, which were not part of the African Union force. But Muslim militias and mercenaries remain a threat.

A government has been established under an interim president, Catherine Samba-Panza, who is not connected to the militants of either side. But her administration, packed with her relatives and associates, is proving ineffective; U.N. Secretary General Ban Ki-moon, who recently visited the country, fairly described it on the opposite page on April 14 as “at ground zero of governance.” It needs funding and technical help if it is to get police, courts and prisons running again.

Encouragingly, the European Union has agreed to send 1,000 reinforcements to back the French — whose intervention in the country followed successful but simpler operations to rescue Mali and the Ivory Coast from anarchy. Also promising is the relatively broad mandate granted the peacekeeping force by the Security Council. It will have authority not only to protect civilians and humanitarian aid deliveries, but also to monitor human rights abuses and help national authorities arrest those responsible for atrocities.

Much more aid, however, is needed. A U.N. appeal for $547 million had attracted only about a fifth of that amount by the beginning of this month. The Obama administration has provided or pledged $67 million in humanitarian assistance as well as $100 million for the training, equipment and transport of the African Union mission and $7.5 million for human rights and other programs. That’s generous support, but the needs of the Central African Republic are virtually bottomless.