After the Macondo well exploded in the Gulf of Mexico, it was easy enough (on your choice of screen) to see a flaming oil platform, the very sea itself set afire with huge plumes of black smoke rising, and the dark smear of what would become five million barrels of oil beginning to soak birds and beaches. Infinitely harder to see and less dramatic was the vast counterforce soon at work: the mobilizing of tens of thousands of volunteers.