Story highlights If there is an issue about which Brown is most passionate, it is climate change

It's also been a galvanizing, rallying cry for others in the opposition to the Trump administration

San Francisco, California (CNN) In the space of 24 hours, California Gov. Jerry Brown flew out of China after signing bilateral climate change deals and meeting with President Xi Jinping in Beijing and returned home to host the German environment minister in San Francisco.

Showing almost no sign of jet lag, the governor, 79, punctuated every word from his news conference podium as he declared America remained in the Paris accord, despite the White House withdrawal from the global agreement.

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German Environment Minister Barbara Hendricks grinned as she thanked the governor's hospitality and pledged to work with Brown as her American counterpart to fill the void Washington had left.

"We're in a very unusual, unprecedented situation in America," said Brown. "We've never had a President like Donald Trump. In effect, he's standing against the world and he won't be able to stand much longer. We're ready for battle."

If there is an issue about which Brown is most passionate, it is climate change. That's pushed him from an already vocal opponent of the administration to shouting his opposition. He's taken to saying the President is AWOL on the issue and called the Paris accord withdrawal "an insane and deviant move."

California Governor Jerry Brown gives a speech during the Clean Energy Ministerial international forum in Beijing on June 6, 2017.

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