Crude oil from the "BP oil spill" in the Gulf of Mexico has officially hit the coast. Louisiana's first line of defense is a string of coastal wetlands already so fragile that experts are worried the oil spill could prove "the straw that broke the camel's back."

According to the New York Times, these wetlands have been sinking at the rate of one football field an hour for decades. Levees on the Mississippi river, pipeline canals dug by oil companies, and Hurricanes Katrina and Rita have battered the marshes to the point of disappearance. For coastal residents, the wetlands are vital for protecting against hurricanes. The minimal resistance they mounted to the most recent attackers are testament to how weak they've become.

Vegetation holds wetlands together. When marsh grasses die, the soil beneath them disperses and sinks into the ocean. Conservationists are worried that the crude oil from the spill will smother vegetation past its natural ability to cope, sending the lands underwater once and for all.

Obama will visit the spill on Sunday morning, nearly two weeks after BP's oil rig first exploded. Recent clean-up efforts have been hindered by high winds and choppy seas, and attention has shifted to the first animal victim of the spill: a lone Northern Gannet seabird found slick with oil. 

William Dietrich, an environmental reporter who won a Pulitzer for coverage of the Exxon Valdez oil spill, predicts that quantifying the environmental damage will degenerate into legal battles reminiscent of the 1989 Alaska spill:

At issue will be how much wildlife and seafood was present before the spill, and how much was lost. The inventorying will pit legions of scientists from the Gulf states against legions of scientists from BP...

That means the more the Gulf states know about their coastal environment, the more money they will collect at the back end. They'd better hope they haven't gutted their environmental agencies, because they need them right now.