I thought I've seen your question 2 or 3 times before. Here is your conclusion:
Year 2222 (or not too far future, up to you to decide)! US (and all other countries on earth) bankrupted them self to the ground, people dying from hunger, illnesses, cold, etc. Government doesn't have power to help its citizens with protection, food, health, education, etc. anymore. Basically there is almost stone age and total anarchy around.
Climate still didn't change, no matter what humanity did, trying to stabilize it to warming or cooling. It still has same its own pattern based on Sun activity and distance of the planet Earth from the Sun.
Humanity fills frustrated and defeated. They now fill so miserable, kind of like ants, who try to push the mountain.