It took futuristic technology to achieve one of the worst ecological disasters on record. Without such technology, after all, BP couldn’t have drilled the Deepwater Horizon well in the first place. Yet for those who remember their environmental history, the catastrophe in the gulf has a strangely old-fashioned feel, reminiscent of the events that led to the first Earth Day, four decades ago.

And maybe, just maybe, the disaster will help reverse environmentalism’s long political slide  a slide largely caused by our very success in alleviating highly visible pollution. If so, there may be a small silver lining to a very dark cloud.

Environmentalism began as a response to pollution that everyone could see. The spill in the gulf recalls the 1969 blowout that coated the beaches of Santa Barbara in oil. But 1969 was also the year the Cuyahoga River, which flows through Cleveland, caught fire. Meanwhile, Lake Erie was widely declared “dead,” its waters contaminated by algal blooms. And major U.S. cities  especially, but by no means only, Los Angeles  were often cloaked in thick, acrid smog.

It wasn’t that hard, under the circumstances, to mobilize political support for action. The Environmental Protection Agency was founded, the Clean Water Act was enacted, and America began making headway against its most visible environmental problems. Air quality improved: smog alerts in Los Angeles, which used to have more than 100 a year, have become rare. Rivers stopped burning, and some became swimmable again. And Lake Erie has come back to life, in part thanks to a ban on laundry detergents containing phosphates.