I believe that it's the only moral thing to do.
In schools we learn that obeying is good, disobeying is wrong.
Well look at history, all those order followers that drop bombs, torture people, millions died in gulags and concentration camps. It would have been better if all those would have followed their own conscience instead of "just doing their job just following orders".
Edit Oh I see the reply is double. It gave an error the first time so I pushed the post button again.