The human race is a very selfish one. We always tend to think in terms of our own benefits. Some people spilt tonnes of oil in the sea; they have already lost millions of dollars by doing so and sending ships and people out there to clean up will actually cost them A LOT of money. How is this of benefit to them? Many aquatic creatures will die and many marine animals will perish in this unfortunate incident but how does it concern them? Why would they care about other beings when it's not their own kids and spouses' lives at risk?

What they have been overlooking here is that Global warming is a serious matter. It's manifested itself into several forms in the United States of America such as- say Katrina(The cyclone), etc... Maybe they would understand the importance of a clean and green environment when the apocalypse(non-biblical but due to global warming) would be inevitable.

To answer your original question, Obama will not clean the mess up as this would mean spending another few millions of U.S. dollars into something which will not be of any financial benefit to them.