I returned recently from my second visit to the Sudanese region of Darfur, where I traveled to refugee camps, villages and rebel-held territories. While the Middle East and Iraq grab headlines, beneath the media radar screen "something very ugly is brewing" in Darfur, United Nations Deputy Secretary-General Mark Malloch Brown has warned.

Since 2003, the Sudanese government and the Janjaweed, a government-backed Arab militia, have killed hundreds of thousands in Darfur. Now the crisis has come to a terrible fruition. Large-scale military assaults have been launched recently by the genocidal Khartoum regime. Helicopters and warplanes are crossing the skies of north Darfur, bombing and burning villages without regard for human life and leaving crops destroyed, cattle killed and civilians dead and displaced.

The camps I visited, with seas of plastic sheets sprawled across the baked desert floor, are cauldrons of despair, terror and rage. Desperate pleas for protection singe my memories of my time among these increasingly abandoned people. At Zam Zam refugee camp, a woman holding a small child implored me, "Help us. We need help. We have nowhere else to go. We are going to die. We will all be slaughtered."

The need for a robust U.N. peacekeeping operation could not be more evident. The U.N. Security Council passed a resolution based on a proposal by Secretary-General Kofi Annan for 24,000 troops and security personnel.

Regime defiant
But the government of Sudan has rejected the proposal, just as it has flouted a number of previous U.N. resolutions. Unless the U.N. can find the political will to deploy protection forces without the consent of Khartoum, the fate of Darfur will remain in the hands of those responsible for the immeasurable suffering and terror of 2.5 million displaced people.

The need to deploy such a force has been made clear to Sudanese President Omar el-Bashir. But he has brazenly asserted, "We are determined to defeat any forces entering the country, just as Hezbollah has defeated the Israeli forces."

While Bashir does not want U.N. intervention, the chorus in refugee camps and the remote rebel-held territories of Darfur was the same: "U.N., U.N., we need U.N. peacekeepers!" Rations of hope are meager in Darfur, but in those moments I did see eyes alight with hope.

Bashir's position is unwavering, yet the world continues to use Sudan's refusal of a U.N. force as an excuse for inaction.

"As long as the government of Sudan does not accept a (U.N.) mission, there will not be one. It's as simple as that," said Jean-Marie Guehenno, undersecretary-general for Peacekeeping Operations.

Wooing won't work
But I have looked into the eyes of despair itself. As world leaders continue their diplomatic wooing of the regime, conditions in Darfur have gone "from really bad to catastrophic," said Jan Egeland, the U.N.'s top humanitarian official.

Humanitarian organizations have no access to hundreds of thousands of helpless civilians. The badly under-equipped African Union, the only peacekeeping force on the ground, has ceased to function meaningfully. Still, the defiant Sudanese government last week ordered the AU force out of Darfur by Sept. 30 unless it agrees not to be part of the U.N. force.

To date, as many as 500,000 people have died. Hundreds of thousands more will surely die without international protection.

As time runs out for Darfur, we must demand that the international community provide all resources — including military — necessary to protect innocent civilians and courageous humanitarians.

In the face of the first genocide of this century, knowing full well what is required to halt continuing ethnic slaughter, we have been unwilling to take the necessary actions. This is a defining moment.

Even now, from the distance of more than a decade, we look back at Rwanda and despair at our abysmal failure to act.

In Sudan, when the history of this terrible episode in human destruction is written, will we have any less reason to despair about our acquiescence before the ultimate human crime?

Mia Farrow is an actress and goodwill ambassador for UNICEF.