Not trying to pick a fight here, but I am curious as to what about this rule is so negative, and what is liberal about working to improve the environment in an economical way?
The "science" upon which the EPA rules on diesel emissions are based have proven to be false.
Does that concern you?
IOW, do you think that the government should have to have some logic behind forcing individuals and companies to change what they are doing, or do you think that it's OK for America to be a fascist state with the government controlling industry?