We saw that external costs exist and they are directly related to pollution. Inevitably, to fight pollution we need to invest capital in order to improve our equipment and repair the damages that are already done. One thing we can’t ignore is that we are going to pay for the damages no matter what, even if we don’t want to fight pollution, because of the natural catastrophes, dryness, diseases, etc.
As for global warming, we need money to replace the old equipment so we could start reducing gas emission. The idea of investing in new equipment is to avoid additional costs that we could face in the future. When we often hear the comment “the cost of doing nothing will be greater”, it means that if we keep business as usual, the consequences of regular pollution will affect drastically the nature, and therefore, repairing the damages later on will require much more effort then the amount we need to invest today. Unfortunately, cleaning the planet from the gas emissions is a cost our generation has to cover because no one assumed it earlier.