"Always will be"? That seems excessively pessimistic. Why do you think that?
We knew about fossil ressource depletion in the 70s and about the effect on Co2 on temperature in the 19th century (the earliest article i've found is from 1912, but the science was available earlier).
We could have invested in better infrastructure and better housing since at least the 90s, and pushed the research towards material science and fission/fusion after the 80s. Pushed to create more public researcher jobs would've been nice too (most innovation is built on top of public research, and forming researchers is nice for the industry too)
Instead we built more stuff for cheaper (by outsourcing the production and crippling the productive apparel of small third-world countries).
1. Whether it's physically possible to accomplish this. The natural course of the Earth is to enter into another ice age at some time in the future. Is there a way for us to prevent this from happening, without compromise or sacrifice? Without side effects? I don't have the needed knowledge to disqualify that possibility, but I lack the confidence that it is an achievable outcome. I imagine the closest comparison points we have for such efforts is our attempts to introduce non-native species to impact local flora and fauna. And that hasn't typically gone well in the past.
2. Whether having such control is at all possible. If we develop the means to control the climate to such an extent, I can only imagine what that would lead to in terms of global politics. It has to be something that the entire planet is cooperative about, and hope that no personal agendas try to push for misuse of the technology.