A day in Darfur is as close as you'll ever get to walking back and forth through the looking glass. In Darfur you might, as I did, witness an eight-pound 3-year-old who will be dead in a few hours; then the next day you're back in the United States, where 60 percent of the population is overweight.

This is something few can grasp even if they see it. I spent a troubled period recovering from injuries received in the Vietnam War. After that I believed I was immune to personal tragedies. I'm not. Darfur is as close to hell on earth as we can imagine.

Aid workers have seen hungry people before, but even those directly involved in emergency humanitarian assistance seldom encounter starvation and virtually never witness the starvation of tens of thousands of people.

The cruel irony in all of this is that the world has been down this road before, in both Somalia and Rwanda.

In fact, I thought I'd seen it all before going to Darfur last month. I'd been to Baidoa, Somalia, in December 1992 and to Rwanda two years later. In both countries I saw mass starvation and murder. But what I saw in Darfur is worse. I walked into camps and saw women and children in every state of human misery. Too far gone to eat, many would be dead by morning. Just when I thought it couldn't get any worse, I heard about the systematic rape of women. It was not two or three women telling me this. Virtually every woman I met in a camp had a story of brutal violation. This is what the world faces in Darfur.

The United Nations has given the Sudanese government 30 days to disarm the mounted militias known as Janjaweed and bring the war-torn Darfur region under control. That's 30 days too late for more than 13,000 women and children. More than 440 people a day are dying from starvation in Darfur. And this does not include people who will be murdered outright.

In addition, the Sudanese government is in armed conflict with two forces, the Sudan Liberation Army and the Justice and Equality Movement, in Darfur. It is also trying to conclude a critical peace agreement between North and South Sudan. Is it realistic to expect that government to also disarm a vicious Janjaweed militia and facilitate international relief?

Although this is the worst humanitarian disaster in the world right now, the United Nations has received only $158 million of its $350 million donor appeal for Darfur. While catastrophic loss of life is occurring, the international community is buying time. For what, exactly? How many people have to be killed or starved to death before the world acts? The international community has the resources to mount a swift response, but thus far it has lacked the will to stop the slaughter. Rich governments must respond, both for the immediate crisis and for the long term.

The Security Council has invoked Chapter 7 of the U.N. Charter and endorsed deployment of African Union cease-fire monitors and troops to protect the monitors. To date, a mandate has not been endorsed to provide protection for the Sudanese population and the security required for humanitarian assistance. This could be mobilized under the auspices of the African Union, with support from the international community.

Since my return, my heart has sunk as arguments intensified about whether the Darfur situation should be defined as genocide or ethnic cleansing, and whether sanctions should be applied. What's happening in Darfur is the wholesale slaughter and rape of unimaginable numbers of human beings. Sudan is a sovereign nation. But it has utterly failed in its responsibility to protect its citizens. Definitions should be left to the dictionary -- now is the time for action.

The situation in Darfur is not an American issue. It is not a European issue or an African issue. It is the most fundamental statement of what we stand for as members of the human race. The slaughter and rape of hundreds of thousands of people is not acceptable by any standard of humanity. If there is ever a time the international community has to come together, and do so in a decisive fashion, it is now.

The writer is CARE's security director and a retired Marine colonel.