Right now the U.S. has a very real opportunity to transform our economy from one running on fossil fuels to one largely based on clean energy. We are developing the technologies and know-how to accomplish this. We can build whole new industries and create millions of new jobs. We can reduce energy costs, both at the gas pump and at home. We can improve our national security. And we can put a big dent in climate change. With strong leadership we could be moving forward on an aggressive but realistic timeline and an approach that balances costs with real economic gains.