There was already simmering political fallout from the storm. Republican Gov. Bobby Jindal, who canceled his trip to the convention in Tampa, said the Obama administration's disaster declaration fell short of the federal help he had requested. Jindal said he wanted a promise from the federal government to be reimbursed for storm preparation costs.
"We learned from past experiences, you can't just wait. You've got to push the federal bureaucracy," Jindal said.
FEMA Administrator Craig Fugate said such requests would be addressed after the storm.
"We wanted to make sure direct federal assistance got out first," Fugate said.
Obama promised that Americans will help each other recover, "no matter what this storm brings."
"When disaster strikes, we're not Democrats or Republicans first, we are Americans first," Obama said at a campaign rally at Iowa State University. "We're one family. We help our neighbors in need."
While politicians from both parties were careful to show their concern for those in the storm's path, Gulf residents and visitors tried to make the best of the situation on the ground.
In New Orleans' French Quarter, Hyatt hotel employee Nazareth Joseph braced for a busy week and fat overtime paychecks. Joseph said he was trapped in the city for several days after Katrina and helped neighbors escape the floodwaters.
"We made it through Katrina; we can definitely make it through this. It's going to take a lot more to run me. I know how to survive," he said.
Tourists seemed to be taking Isaac in stride.
Maureen McDonald of Long Beach, Ind., strolled the French Quarter on her 80th birthday wearing a poncho and accompanied by family who traveled from three different cities to meet her in New Orleans to celebrate.
"The storm hasn't slowed us down. We're having the best time."
Maureen's son, Bob McDonald, said the group considered canceling the trip, but the thought passed quickly.
"We just figured why not get the full New Orleans experience, hurricane and all," Bob McDonald said. As they walked through the French Quarter Tuesday morning, they took pictures of media trucks parked near Bourbon Street and businesses boarding up windows.
But farther east along the Gulf, veterans of past hurricanes, made sure to take precautions.
At a highway rest stop along Alabama's I-10, Bonnie Schertler, 54, of Waveland, Miss. Summed up her decision to leave her home on the coast for her father's home in Red Level, Ala. after hearing forecasters warning that the storm could get stronger and stall.
"I left because of the 'coulds,'" said Schertler, whose former home in Waveland was destroyed in Hurricane Katrina. "I just feel like the storm may stay for a few days and that wind might just pound and pound and pound and pound," she said.
"A slow storm can cause a lot more havoc, a lot more long-term power outage, 'cause it can knock down just virtually everything if it just hovers forever," she said.
Those concerns were reinforced by local officials, who imposed curfews in Harrison, Hancock and Jackson counties. The Mississippi Gaming Commission on Tuesday ordered the closing of all coast casinos, which are on or near the water.
"This storm is big and it's tightening up and it sat out there for 12 hours south of us and it's pushing that wave action in and there's nowhere for that water to go until it dissipates," said Harrison County Emergency Operations Director Rupert Lacy.
All along U.S. 90 in Harrison County, families stood at the edge of the waves to gawk. The Mississippi Sound, protected by barrier islands, is often as still as a lake, but Isaac began stirring breakers before dawn, as it pumped a storm tide toward the coast. Police struggled to clear public piers where water was lapping at the boards, and resorted to bullhorns to try to get sightseers to leave the beach. But people were still coming down to the edge to take a look around 2 p.m., as it began to rain heavily in Gulfport.
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