Sometimes life has a way of intervening while one is making other plans.
Obama didn't plan for his legacy to be the world's worst oil spill in the Gulf of Mexico. But it is indeed his legacy. I'm sure he'll try to duck it. But this is Obama's oil spill.
Obama has been in office for a year and half. If he'd wanted to change policies on off-shore drilling, he had time to do so. For instance, a President could well have called for a moratorium if they felt safety issues needed to be reviewed. In fact, we know Obama knows that he could change policies if he wants to, because he's in the process of doing so .... to expand offshore drilling in the Gulf.
How many Obamabots realized last election that they were voting for "Drill, Baby, Drill"? The key is to learn the lesson from it.