It starts here: Erza Klein lists seven reasons why it's too late.
1. We waited too long. Self-explanatory.
2. The people most affected don't get to vote. For those of you who read Collapse by Jared Diamond, this is the number one reason societies collapse.
3. We're bad at sacrificing now for the future. As Neil Degrasse Tyson and Thomas Piketty keep pointing out, that is a design feature of capitalism.
4. The effects are not reversible. It's not like if we just stop burning carbon, things will go back to the way they were. These changes are effectively permanent.
5. The Republican party. Self-explanatory.
6. International cooperation is too hard. Here I think he is wrong; if America were leading the way on this, we could actually pull it off. There is a value to having a military roughly equivalent to the rest of the world combined; people listen when you speak. If the USA were of one heart and mind on this, we could make it happen. But see #5.
7. Blind faith in magic doesn't work. But I guess this is really just #5, again.
What am I doing about it? I only had one child, we own a single car, and I will be buying a house at least 10 meters above sea level.