When John Kerry was secretary of state, he said if the U.S. took drastic action to eliminate all domestic greenhouse gases, it would not be enough to stop the global warming. We have global warming, and stopping it requires a global response.
To be successful, China, India and especially the developing countries must make drastic changes to their economies. There is little indication of their doing that.
Hence, global warming will continue and increase, so the United States should prepare.
Fortunately some areas of the country are preparing, plus the current administration has started a program to enhance preparedness for the expected effects of global warming. The U.S. should do what it can to make cost-effective changes to reduce carbon dioxide and methane releases.
Preparedness is required for protection against sea level increases. The whole Southwest must work on water resources, crops need to have increased tolerance to climate changes, etc.
Immediate action must be taken for major changes to the Atlantic Coast areas, especially Florida, the Gulf Coast, South Carolina and New York. This is a better way to spend government funds than most CO2 reduction approaches at the local level.