The 50 states that make up the U.S. don't get to set their own foreign policies (neither do Canadian provinces).
But that doesn't necessarily prevent them from working with other countries on matters of mutual interest.
And that's just what California is doing in an agreement announced this weekend that expands its efforts to battle climate change as the Trump Administration moves the U.S. decisively away from national efforts to do the same.
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German environment minister Barbara Hendricks said on Saturday that California will back the work of the "Under 2 Coalition," as will Germany itself.
The coalition was reported that day by the Reuters news service, among others.
The name of the group refers to the goal established by scientists of keeping the rise in global temperature due to carbon emissions under 2 degrees Celsius above pre-industrial levels in 1750 or before.
CA Governor Jerry Brown, State Sen. Alex Padilla, and Google's Sergey Brin beside an autonomous car
That number, it is hoped, could avert the worst of the predicted effects of climate change, although far from all of them.
Hendricks negotiated directly with California governor Jerry Brown on the joint agreement.
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California alone generates $2.4 trillion of yearly economic activity, which would rank it as the sixth largest country in the world by gross domestic product, ahead of France and Brazil based on 2015 data.
Germany, meanwhile, is by far the largest economy in Europe, significantly ahead of both the U.K. and France. Together, the two bring a significant swath of the world's economy into efforts to fight climate change.
President Donald Trump (Photo courtesy DoD)
"We cannot achieve our climate goals without the engagement of local and regional communities," Hendricks said.
"That has become even clearer after the U.S. withdrawal from the Paris climate agreement."
Trump's pledge to withdraw the U.S. from the Paris agreement has generated widespread global criticism, seemingly more than the administration anticipated.
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His attacks on Germany as a bad actor for its trade surplus in luxury automobiles, despite BMW and Mercedes-Benz plants in the U.S. exporting hundreds of thousands of high-value vehicles around the world, produced further resentment in Germany, a major trading partner.
With California having the ability to set its own emission standards, a statewide commitment to reducing energy use overall and significantly boosting renewable energy, and the largest single market for vehicles in the U.S., it holds significant sway in setting policy for the U.S. overall.
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