For weeks Haiti's political crisis has posed a latent threat to the 7 million inhabitants of the hemisphere's most impoverished country.
But now the political opposition's rejection of a US-brokered power-sharing plan, and President Jean-Bertrand Aristide's warning of an exodus of boat people for the shores of Florida, have the prospect of a humanitarian crisis looming larger.
So far, rebels advancing southward toward the capital of Port-au-Prince are concentrating their ire on police stations and other government offices. But some food warehouses maintained by international agencies have been ransacked, and supply lines have been disrupted.
As the rebels talk of taking the capital by Sunday, fears of violence and food shortages among the population are growing.
Florida officials, including the state's two Democratic senators, are warning that the Bush administration's refusal so far to consider sending in security forces to restore calm could result in a major exodus. But Haiti experts note that leaving the country by boat takes time to plan - and before people have a chance to leave, the fast-moving crisis could result in deteriorating conditions for the population.
"I have no doubt there are more people wanting to flee the turbulence, and that will only increase if things get worse as they look like they will. But even if 40,000 people wanted to leave, that takes time," says Lawrence Pezzullo, a former foreign service officer who was the Clinton administration's Haiti envoy. "But famine can threaten quickly if you're unable to deliver food," he adds. "That's very difficult to do in the middle of an insurrection."
Haiti's poverty and meager food production resulting from near-total deforestation have left large numbers of people dependent on food aid. But the United Nations World Food Program reports supplies have been pillaged, while the numbers of people seeking assistance is growing quickly.
"This is a catastrophe in the waiting, because the so-called rebels, who are really thugs with guns, are not letting supplies through," says Ron Daniels of the Haiti Support Project in New York. "With as many as 300,000 people dependent on food assistance just in the north, things can turn disastrous quickly."
The Bush administration continued to rule out military intervention Wednesday but was clearly surprised by the political opposition's rejection of the power-sharing plan. The administration's careful response reflects recognition that a botched Haiti crisis in an election year could have repercussions in several states, including Florida, where Haitian immigrants are concentrated and any new exodus would be felt.
The US restored Mr. Aristide to power in 1994 as the country's democratically elected leader. But since that time, and despite his reelection in 2000, he has lost support from Haitians as corruption and cronyism have spread, and from international backers as he has failed to implement long-promised reforms.
The US now finds itself in the unenviable position of insisting on a political solution that includes Aristide, since its promotion of democracy in the region bars encouraging an outcome that does not at least on its face uphold the rule of law.
Yet the US is also interested in not seeing a repeat of the exodus of Haitians that occurred in the early 1990s, when more than 20,000 fled by boat to the US. Many were temporarily housed at the US base in Guantánamo. Mr. Pezzullo says a repeat of that step would raise fresh criticisms of the Bush administration's human rights practices. "That [exodus] scenario, with all its ramifications, is what the administration wants most to avoid, and that's why Aristide is tweaking their nose with it," says Pezzullo, referring to the leader's warnings.
The only solution to Haiti's recurring crises will be "sustained constructive engagement" by the international community in building the country's democratic institutions and assisting development, Mr. Daniels says. "But that won't be possible," he adds, "if these armed gangs are allowed to take over the country."