The leak hasn't even been stopped yet. Let us hope they manage to do so today. It isn't even just the oil, as the dispersant seems to create these underwater plumes, comprised of droplets of oil, dispersant, and water of course. These are swirling around in the water and probably killing tons of fish. That isn't a good thing when people say the fish population is already declining. Much worse than that, your natural resource possibly just made it into our food supply in concentrated amounts.
It has already hurt Florida tourism. It has already hurt Louisiana fishing. How many businesses were teetering on the edge? How many will fail soon? What are the long term repercussions of that?