I agree there is nothing we can do to prevent the next 30 years or so of climate change. However, there is plenty we can do longer-term. Step 1: USA via coali

I agree there is nothing we can do to prevent the next 30 years or so of climate change. However, there is plenty we can do longer-term. Step 1: USA via coalition (or alone, it doesn't matter) goes Nuclear (Fission). Global energy consumption is 17.4 Terawatts. About 4 Terawatts of that is us. We therefore need about 4000 nuclear power plants to cover our usage (which, given the economy of scale, would probably cost about 4 Trillion or so). It would take 15 years to build them out, so that's about $280 billion a year. Not particularly expensive, given the overall federal budget is $6 trillion. In addition to domestic construction, we offer generous construction deals to all other countries at-cost with shared IP. Any country can sign up, and the US will use it's hegemony to backup all deals in a "too big to fail" kind of way. Note that we only need about $24 trillion to build out power for the rest of the world, which again isn't a substantial component of anyone's budget (except for developing countries, for which we would just provide the reactors for free/via loan schemes). China will probably do it themselves, so that's like another 5TW capacity we don't need to build. Step 2: We change out the infrastructure. Massive funding, drowning-in-money level funding for Hydrogen aircraft. Massive funding for electric cars & electric grid improvements. Build out HSR between all cities & build out public transit to sap down air travel / car travel. Cut energy use & de-carbonize. Step 3: Turn the CO2 in the air back into fossil fuel, or capture it into some other form. We build 17 TWatts of nuclear capacity, so we have plenty of energy. We need only scale up the chemical processes for doing the conversion. Once completed, we can now "tune" CO2 levels, giving us a lever for global weather control. This will likely be a useful tool for humanity & will let us dynamically control mean surface temperature.