It was unknown that emitting greenhouse gases caused...
The developed world is mostly to blame for climate change
It was unknown that emitting greenhouse gases caused climate change until the 1980s – over a century after the industrial revolution. Developing nations were not initially aware of the damage they were causing, therefore the harm was unintentional. It is unfair to retrospectively punish these nations for something that was unknown to be harmful when it was done. The responsibility should therefore be based upon either current emissions or at most emissions from the period in which the damage caused was known and emissions could have been reduced.