Creating a carbon tax (a tax on fossil fuels) to help reduce our carbon emission. The Unites States is a world leader in carbon emissions and we must act on the matter and become an example for other nations to follow. Failure to lower our carbon footprint on Earth, will result in instabiltity in our climate, and mass extinctions of many species of animals.
Doing so could help lower other taxes such as payroll taxes amongst other things. This also helps boost sales of electric cars and raise funding for renuable energy sources such as solar and wind.
As previously stated, and as the leader of the free world, we must be the first to act to set an example for the rest of the world.
Watch: https://www.youtube.com/watch?v=90CkXVF-Q8M&feature=share