明白為什麽美國柴油車少了；正規的美國式做法是

U.S. regulators however say they are crafting rules that should avoid pitfalls – including rising EU NOx levels despite quadruple-strength restrictions against them.

 

http://www.hybridcars.com/will-america-avoid-europes-clean-diesel-problems/

 

這就是lobby group，