From Batman Begins
You're gonna destroy millions of lives.
Ra's al Ghul
Only a cynical man would call what these people have "lives," Wayne. Crime, despair... this is not how man was supposed to live. The League of Shadows has been a check against human corruption for thousands of years. We sacked Rome, loaded trade ships with plague rats, burned London to the ground. Every time a civilization reaches the pinnacle of its decadence, we return to restore the balance.