Clearing the Air.

New Delhi's 13 million souls and its claptrap vehicle fleet of 2 million help produce some of the world's most horrid smog. Two years ago, India's Supreme Court decided that it could fix that. It decreed that public transport vehicles in the city must use compressed natural gas (CNG). The deadline for the switchover was April.

So New Delhi's air must be much improved by now? Not exactly. When the deadline hit, mobs of jobless bus workers burned five buses and damaged another 39. Generic rioting broke out. A bus fleet of 13,000 was cut to 1,400. The city ground to a halt.

The court responded with a 10-day extension, giving the city government a little more time to issue temporary operating permits to vehicle owners who'd placed orders for CNG vehicles or conversion kits but didn't have them installed yet. But the court can do nothing about the cost. Some $114 million must be spent buying new buses, refitting old ones, and finding ways to deliver the new fuel to would-be users. Only 43 gas stations in New Delhi can now sell CNG, and everyone knows that isn't enough.

"I spend at least four hours every day now waiting in queues," Naresh Chand, 60-year-old owner of a new CNG-compliant auto-rickshaw, complained to The Washington Post. "My earning has dropped from $6 a day to $2 now because of these queues. What do I feed my family? First I have to live. I will think about clean air later."

That, in handy capsule form, is the issue. How do poor countries move to create what are in effect luxury public goods, like clean air? A toughie to be sure, but edicts from on high usually do more harm than good.