What if the CO2 in the air is causing climate change?

This is for the people who don’t believe that at least some of the climate change is caused by man.

What if it is true that CO2 we put into the air is causing our climate to change? Is it worth the risk not to err on the side of caution? Most of the activities pollute the air or harm the environment in some way anyway. Climate change is just a possible additional side effect.

Let’s say 20 years from now you know that the alarmists were right. What are you going to do then? Just assume for a second we are in the future and that is the actual case.

This Q is not to argue about whether climate change is real or whether human beings are making it worse. This Q is a hypothetical question about if it is indeed proven what will the naysayers feel and do?