I'm against Diesels for a different reason...
Diesel fumes are carcinogenic... they also contain Dioxin (Love Canal anyone?)
Very very bad. About 4 months ago I read a listing of the most cancer causing chemical compounds that are found in abundance, and Diesel fumes were #2. Asbestos I think was number 1, while second hand smoke was number 7. It was in an article in Time magazine.
Diesel fumes are bad, very bad.