> The US is also much more concerned with air pollution that affects human health.

What makes you say that? The EU has made plenty of decisions that are aimed at improving air quality which has a direct impact on health, I don't see the US taking the lead here, in fact there are quite a few cases where the EU has lead and the US has definitely not followed.

There is a strong push from US automotive companies against diesel simply because they don't really have the engines, the ones they do sell are quite often sourced from other companies (such as Cummins, which is definitely a fine engine). In the US diesel is for trucks and tractors and gas for light vehicles with only some pick-ups and large SUVs available with both fuel options from domestic manufacturers.

The VW scandal is definitely very bad for the diesel engine but it's not the engines per se that are the problem here, diesel can run clean, it's just that VW decided to cut corners and then cheat on the tests when they found that their corner cutting made it impossible to comply (what amazes me about the whole thing is that it took this long to find out they cheated so massively).

The Euro 6 standard allows 0.08 g/km of NOx emissions for passenger diesel; the EPA allows a fleet average of 0.04.

The U.S. certainly is ahead of Europe on the regulation of toxic emissions, and European cities are much more likely than American ones to have dangerous levels of pollution:

http://www.nytimes.com/2014/12/31/upshot/pollution-around-th...

That 0.08 g/km figure is using the 'new european driving cycle' which features unrealistically low loads on the engine, engines are known to increase their NOx emissions quite a bit when under load.

Anyway, NOx is not the only gas that the EU is concerned about, C02 figured very large in the whole reduction program as well.

> That 0.08 g/km figure is using the 'new european driving cycle' which features unrealistically low loads on the engine, engines are known to increase their NOx emissions quite a bit when under load.

Doesn't that lend further support to the point that U.S. regulations, while also obviously not perfect, are stronger in this area?

> Anyway, NOx is not the only gas that the EU is concerned about, C02 figured very large in the whole reduction program as well.

But you were challenging pwthornton's assertion that "The US is also much more concerned with air pollution that affects human health." While CO2 emissions are undesirable, NOx and particulates are what actually kill people in polluted cities.

Diesel can run clean, it's just they'll be far more expensive and produce far less power than their gasoline alternatives. The entire european diesel wonder was that engines of similar power were able to offer better milage than those of gasoline. However this has been all due to substantially worse emissions. For VW to bring emissions down to regulation the engines will produce significantly less power and customers will no longer want to use them.

Simply put, this is the death of diesel for automobiles. It's just a dead end technology that has thrived by cheating. Europe was dead wrong in their automotive efficiency priorities and public health has suffered as a result.

VW is not the only supplier of diesel engines and the other manufacturers to date have not been proven to cheat (though it may very well be that Mercedes, BMW or some other company will end up in the same docket besides VW when all is said and done as far as I know there is no proof of this at the present).

So this not 'the death of diesel for automobiles', though it may definitely be the death of diesel sales for VW in the United States.

As for public health suffering: the best way to improve public health is to promote cycling, reducing the total mileage a person spends driving during their life is the biggest public health benefit you could score and from that perspective whether you focus on diesel or petrol or CO2 emissions versus NOx as the most important is time, effort and resources wasted.

I'm trying to imagine everybody that I see cycling here driving a vehicle and the resulting pollution would be astounding, especially for short trips (when the catalytic convertor has not yet warmed up).

The performance of diesel car's in recent years has been quite literally miraculous. If you knew a little bit about engines you would know that something was a off for there to have been such a dramatic improvement in power, efficiency, and emissions at no apparent cost. Diesel has traditionally not been the most powerful choice so for the power to be comparable was very fishy. Now just about every single diesel manufacture is being investigate from Europe to Japan for cheating. Initial reports are already showing that Mercedes, Toyota, and plenty of other players all have significantly worse emissions and efficiency.

Europe is cracking down on diesel, and they're going to remove tax breaks that cheating manufactures enjoyed. Anne Hidalgo, the mayor of Paris, is talking about ban these vehicles from the city by 2020. This is the end of european diesel cars.

If you want to get rid of diesel, get rid of long haul trucking. Maybe also look at shipping's use of low grade bunker fuel, which pollutes more than all passenger cars iirc.