In just five years, California has implemented significant energy policies that America must now embrace. We’ve decided to increase the amount of renewable resources we rely on for our energy, to encourage the growth of green business, to establish a first-of-its-kind low-carbon-fuel standard, and to reduce our greenhouse-gas emissions. These measures are ambitious but essential. And we are proving that we can boost the economy at the same time.

By 2020, a third of America’s energy must come from renewable resources. That’s the goal we are working toward in California, and I don’t see why other states should settle for less. Three years ago, when I urged California to increase its reliance on clean energy, some critics said my approach could harm the economy. Back then, oil was trading at $50 a barrel. Those days are over. The question now isn’t whether we can afford the leap but whether we can afford to put off our transition any longer.

America needs to encourage innovation and new technologies with a national policy, modeled on California’s Global Warming Solutions Act, that would create a market for greentech and clean-tech companies. The U.S. should also adopt California’s low-carbon-fuel standards, which will put 7 million electric cars and hybrids on our roads by 2020.

And the next president and Congress need to commit, as California has, to cutting our greenhouse emissions 25 percent by 2025, and then an additional 80 percent by 2050. Right now, worrying about emissions is like worrying about your weight when you haven’t been on a scale in a long time. You can’t manage what you don’t monitor. We need a reliable system of measuring greenhouse gases, and we need to establish a hard cap on emissions.

I want America to stay No. 1. I want us to be the world leader when it comes to biofuel and wind, solar, and hydroelectric power. I want Detroit to be the leader in building the world’s cars. Last year, a billboard in Michigan was part of a campaign accusing California’s emissions standards of costing the car industry $85 billion. It read, ARNOLD TO MICHIGAN: DROP DEAD. But it really should have read, ARNOLD TO MICHIGAN: GET OFF YOUR BUTT.

I can’t state this any more urgently: Washington must follow California’s lead. The challenge of making the U.S. more reliant on clean energy should not sound daunting. It’s simple—it just takes action. I am confident that our next president will take action to ensure we move forward on being energy independent and toward being an alternative-energy beacon to the world.