The BP spill is a failure not just of technology but ideology. That oil flows into the ocean from the deregulatory tide of the last 30 years. President Obama is right to compare the fiasco to 9/11. If he can frame the message more memorably than he did in his Oval Office address, Obama may yet use the largest environmental disaster in U.S. history to speed the transition to a green economy, just as George W. Bush used terrorism to refashion foreign policy. To do so, “deregulation”—once a Reaganite call to arms—must be transformed into an epithet. If the president can’t put the antigovernment, Tea Party types in their place now, when will he? The legacy of the American progressive tradition is on the line.