That's like saying "The fall of moral civilization has always been brought about by those who "eat food on a regular basis"".
Nobody would use "I was just eating food on a regular basis" as a defense against blame for misdeeds, which the GP's quote (referencing the Nuremberg defense and similar things events of disavowing blame for evil acts) would be commenting upon.
How much harm do we cause the enviroment by eating the food we eat on a regular basis?
How many people are killed and lives and futures destroyed by people that ard perfectly justified in doing their jobs?
Evil isn't just for comic book super villians, nor does it require any sort of ill intent at all. Look around at your life, and the choices you and others make and ask (honestly) "who is being hurt", the answers can be suprising and unnerveing.
edit: clarity
> Smugglers want to get drugs to the lucrative American market. > Border Patrol are told to stop them cause drugs are bad. >Politicians enact more border patrol regulations to counteract our strict drug policy.
I'm inferring that OP wants border patrol to be political activists and fight for better drug laws instead of just "doing their jobs".
- Thomas Paine