Well the New York Times is a pretty respected paper. Here’s what they have to say:

When Europeans think of diesel, they think of the very cars — small and smart — that half of them are driving now. When Americans think of diesel, they think of semis and buses and pickups and, perhaps, one of the lumbering Oldsmobiles that did so much in the 1980’s to poison the promise of diesel technology here. Europeans and Americans differ in almost nothing more than they differ in diesel, including different emissions standards and different fuel quality. But in the next few years, as the rules on air quality tighten, Americans need a diesel engine that can meet the stricter standards.

Diesel engines offer more torque and greater fuel efficiency than gasoline engines, and they emit less carbon dioxide, a greenhouse gas. The drawback is that they also emit more particulate matter and nitrogen oxide, which contributes to smog. Honda recently unveiled a new engine that solves that problem, using a special catalytic converter that turns harmful nitrogen oxide into simple nitrogen. Honda plans to introduce this engine in the United States in 2009, which just might give us time to improve the poor quality fuel that keeps diesels here from being as clean and as popular as they could be.

It’s always tempting to hope for a futuristic solution — like the new fuel-cell car Honda also demonstrated the other day — for the very immediate problems of auto emissions and fuel efficiency. But the answer is going to lie in a mix of vehicles — hybrid cars, more efficient gasoline engines, and highly improved diesels. The answer is also going to come from recognizing that strict limits on emissions and mileage penalize only those companies that are too sluggish to compete.

Source: newyorktimes.com