which is worse and why?
You really are trying to draw a moral equivalency between the two events?
Bhopal was an accident, and the company was being run largely by local residents who never intended to harm their fellow citizens.
9/11 was a premeditated act of multiple murder committed by foreign terrorists against locals.
Incidently, well-known Liberal Gretta VanSusterand (host on Fox News) and her husband, both lawyers, made $$$millions by suing Union Carbide over Bhopal. I wonder what the survivors got from the settlement - probably not near what the lawyers got.
Only a terrorist sympathesizer would pose such a question. Please go to the Just for Fun forum on RF Globalnet. They'll love you there.