SACRAMENTO — Gavin Newsom took the oath as California’s 40th governor Monday and instantly challenged President Trump, promising a “progressive, principled” administration that will counter “corruption and incompetence” in the White House.

“It is up to us to renew the California dream for a new generation. And now more than ever, it is up to us to defend it,” Newsom said. “But there is an administration in Washington clearly hostile to California’s values and California’s interests.”

The former San Francisco mayor painted a picture of California as a virtual “nation-state,” one that will push beyond the strictures proposed by the GOP leaders in Washington toward a more progressive future.

“What we do today is even more consequential because of what’s happening in our country,” Newsom said on the west steps of the state Capitol, which were enclosed by a tent against the threat of rain. “People’s lives, freedom, security, the water we drink, the air we breathe — they all hang in the balance. The country is watching us. The world is waiting on us.”