The civil war in Syria—now dragging into its third year—has created a humanitarian crisis of nightmarish proportions. Yet the woman in charge of getting food rations inside the beleaguered country remains, improbably, optimistic. It’s one of Ertharin Cousin’s most winning qualities, and the one cited by Hillary Clinton when the former U.S. secretary of State pressed the United Nations to appoint Cousin to lead its World Food Program (WFP) last year.

While Cousin says her initiation as head of the world’s largest hunger-aid organization wasn’t exactly baptism by fire, she admits that confronting the largest refugee crisis in the history of the Middle East certainly tested her skills. Now, she’s facing a new challenge: Persuading cash-strapped Western donors to keep giving money to feed the burgeoning number of Syrians displaced by the violence.

Arriving in Beirut after daylong talks with Syrian government leaders in Damascus, the 55-year-old—who came to the U.N. after stints in the nonprofit sector and the Clinton administration—had money on her mind. And not just money—she was also occupied with the obstacles being placed in the WFP’s path by both the Syrian government and the rebels, not to mention the sheer logistical challenge of distributing 35,000 tons of food to 2.5 million starving people.

Adding to Cousin’s problems are reports that jihadists from the al Qaeda–affiliated Jabhat al-Nusra have started looting humanitarian aid inside the country. Aid has also been held up at government-controlled checkpoints, and the regime of President Bashar al-Assad has prohibited the WFP from bringing medicines into Syria for distribution by more than 20 partner NGOs.

Cousin also worries about the safety of WFP workers inside the warzone. “They are committed to staying because we know if we leave, the program will stop and people will go hungry,” she tells The Daily Beast.

A former public relations and food-industry executive from Chicago, Cousin worked in various corporate and nonprofit jobs in the U.S., including a stint at supermarket retail chain Albertsons, and as chief operating officer for America's Second Harvest, a national anti-hunger organization. She’s held positions in government and political jobs—serving in the Clinton White House as point person to the State Department and later as a senior adviser to the secretary of State.

Before becoming executive director of the WFP—a post Hillary Clinton lobbied hard to secure for her—Cousin served three years as the U.S. ambassador to the U.N. food agencies headquartered in Rome, earning plaudits for her lobbying efforts to get additional funding for food relief to Haiti following the devastating 2010 earthquake.

For a former American food industry exec, Cousin has taken a surprising line as WFP head, and one that hasn’t pleased U.S. agro-business: she supports a transition away from food aid to food assistance. The difference may seem semantic, but it has big on-the-ground implications and has provoked a contentious debate over the years. In the past much of what WFP did was to supply American-produced food to the world’s hungry, benefiting U.S. agro-business but squeezing out local smallholder farmers and inhibiting agricultural development in impoverished countries.

Now WFP—the U.S. is the agency’s biggest donor— is trying to contract locally with local farmers to supply food, and cutting back on its reliance on American agro-business less. On her appointment in April 2012 Cousin announced: “I think that debate is over. WFP is a food-assistance organization.”

Sitting in a downtown Beirut hotel following a hazardous nighttime road trip from Damascus, Cousin comes across as unassuming and passionate about her job. Raised in the rough West Side district of Chicago, she remarked shortly after becoming an ambassador that her biggest surprise in the job was “when people talk about ‘Her Excellency, Ertharin Cousin.’ You know, I grew up in Lawndale. You’re a long way from there when someone’s referring to you as ‘Your Excellency.’”

She also told the Chicago Tribune: “On my commute back and forth from home to work each day, I drive by the Colosseum, the [Roman] Forum, Circus Maximus … You pinch yourself every now and then … I say, ‘It’s OK, girl. Put the BlackBerry down. Look out the window.’”

Recently, she has had little time to visit Rome as she globe-hops to various hunger hotspots. Her line with her interlocutors in war zones is clear: the WFP is focused on the fallout of conflict and not on the politics that gives rise to violence. It is the message she took to Damascus.

“Whenever you have a crisis that goes on this long there’s fault to go around on all sides,” she says. She believes she secured promises of unimpeded access from Syrian government officials, after she sidestepped attempts by the country’s foreign minister to ensnare her in political negotiations around the American push to kick-start peace talks.

“In the meetings with the government my message was we must have access, and we need the government to ensure that they do nothing to impede our access.”

But the jihadists are a different matter. With al-Nusra listed as a terrorist organization by the U.N., Cousin is blocked from having direct contact with its leaders, having to rely instead on “foreign governments”—presumably Gulf ones—to intercede.

“In the last few weeks al-Nusra has gotten much more strident in diverting our conveys in the Deir ez-Zor area where we have actually had commodities taken and then those commodities were distributed by al-Nusra,” says Cousin. “We cannot afford to have any political group—whichever side they are on—impacting humanitarian assistance and politicizing it.”

Cousin’s biggest challenge, though, is securing more funds. She warns that WFP will run out of money for the Syria operation in a couple of months. Currently, her agency is feeding 2.5 million inside Syria and just over a million Syrians who have sought refuge in neighboring countries.

“The total operation is now costing us 19 and a half million dollars a week. Next month we will go to feeding 3 million inside Syria and about 1.3 million outside Syria and our operational costs per week increase to $26 million. By the end of the year we estimate that we will serve 4 million inside Syria, 3 million outside Syria at a cost of $42 million per week or $7 million per day. We do not have the money for this. We have enough right now to support our activities until the end of August, the first of September.”

The Syrian war has come at an inopportune time for WFP. It feeds 85 million people in 74 countries at a cost of more than $4 billion. The agency was already facing shortfalls in its funding from governments because of the impact of the global financial crisis on wealthy Western nations.

Says Cousin: “We are on the phone every single day talking to donors.”