CARACOL, Haiti -- It was a day full of firsts that began with an aircraft landing that transformed a regional airport into an international hub, and ended with two Haitian presidents sharing a public embrace.

Haiti marked a new day Monday as two of its biggest supporters, the U.S. government and the Inter-American Development Bank, delivered on a $300 million promise to help Haitians in this long-neglected region chart their own destiny.

“In January, this was a construction site without a single structure,” U.S. Secretary of State Hillary Clinton said, standing inside one of several newly built factory shells at the 600-acre Caracol Industrial Park in northern Haiti. “The development of the North represents a new day for Haiti and a new model for how the international community practices development.”

Clinton flew into Haiti aboard a U.S. government 757 just minutes behind her husband, former President and U.N. Special Envoy to Haiti Bill Clinton. The landing marked the first time in more than a decade a large aircraft had landed in Haiti’s second-largest city, Cap-Haitien, thanks to a newly asphalted 7,500-foot runway.

It also was the first time the Clintons visited Haiti together since their honeymoon 37 years ago.

Joined by Haiti’s current and former president, the power couple along with IDB President Luis Alberto Moreno officially opened the job creating zone. It was jointly financed by the U.S. government and IDB.

“This is a symbol of a new Haiti,” President Michel Martelly said, as he touted Haiti to dozens of potential foreign investors who flew in for the event, including Virgin Atlantic founder and British billionaire Richard Branson. Joining the businessmen were several U.S. celebrities who have adopted the country since the devastating January 2010 earthquake killed more than 300,000 Haitians.

Secretary Clinton’s visit came on the same day as the U.S. presidential debate on foreign policy. Haiti, she said, was a foreign policy priority for the Obama administration.

“When I became Secretary of State, I looked at the billions of dollars of foreign assistance that the United States spends around the world and I asked myself, why the results didn’t always create meaningful and sustainable change in the lives of people,” she said. “So we redirected our efforts to work with Haiti, not just in Haiti.”

But for all the hundreds of millions of dollars the U.S. government has spent on constructing the park, recruiting investors and building a power plant and hundreds of houses nearby, Clinton warned that “it’s up to the people and leaders of Haiti to sustain and build on this progress.”

For weeks now, the nearby city of Cap-Haitien and Fort Liberte have been the site of protests. Despite concerns, there were no protests Monday as Clinton was whisked from the airport to the site of the housing development where she peppered U.S. Embassy staffers with questions.

She was joined by both Martelly and former President Rene Préval, who made a rare joint public appearance alongside his successor.

Haiti’s problems such as the lack of electricity by most Haitians, he said, were investment opportunities. Later, Martelly would publicly thank Préval, and at one point pulled him on stage and embraced him. Préval, he said, “was the one who allowed this project to happen.”

Préval’s administration began planning for the park — and the Cap-Haitien airport improvements — long before the earthquake. Plans for the park were kicked into high gear after the devastation when Préval’s economic team, led by then-Economic Counselor Gabriel Verret and a private sector-led government commission, approached Clinton’s chief of staff Cheryl Mills to join forces in recruiting the Korean textile manufacturer Sae-A as anchor tenant.

Last week, Sae-A, which employs 1,050 Haitian workers, shipped its first order: 67,000 T-shirts to Walmart.

“Jobs with salaries that will inject millions of dollars in the local economy,” Moreno said.

But those jobs, Moreno said, will not be at the expense of the environment. Addressing the controversy over the park’s location on fertile land near a fragile ecosystem, Moreno said the IDB has set up a trust fund to help protect the nearby Bay of Caracol.

Meanwhile, Bill Clinton, who kept a low-profile during the day, said during the opening ceremony that “manufacturing matters” and the park was an answer to Haitians’ request not to concentrate all of their economic activities in one area.

“This is the beginning of the flowering of Haiti’s north across every economic sector,” he said, calling the park the “economic anchor for the region.”