On Jan. 1, 2013, the rubber meets the road for AB-32: The cap-and-trade program–the first of its kind in the nation–will be fully enforced, and the country and the world will be watching. If it succeeds in cutting California’s carbon pollution without harming the Golden State’s economy, the law could serve as a model for other state policies–and eventually a national law. If it fails, it could be the last nail in the coffin for efforts to enact a national climate law.

Schwarzenegger knows this. The California law was designed to be replicated by other states. Schwarzenegger, whose legacy was tarnished by California’s plunge into an economic recession under his watch and by a high-profile marital-infidelity scandal, has campaigned heavily since stepping down from office to encourage other states and regions to enact climate policies modeled after California’s, with the aim of building up momentum for national and international climate laws…

He likes to talk about the strategy of building up from the “subnational” level–getting cities, states, provinces, and regions to adopt similar policies–taking action when a national government won’t.

“We’ve always tried to show leadership on the subnational level,” Schwarzenegger said of California. “Since the United States was not coming to agreement on anything, we didn’t want to wait. So we moved. But it’s not something that is for 38 million people. It’s supposed to have an effect worldwide. Because if we do well as a subnational government, then other governments are going to feel that they can also venture out and be more independent, and not wait for their capitals to create action.”