Gov. Arnold Schwarzenegger boasted Wednesday that California's leadership is making environmentalism both sexy and mainstream, not a guilt-driven movement for "tree-huggers" and "fanatics."

"Environmentalists were no fun, they were like prohibitionists at the fraternity party," the moderate Republican governor told a student audience at Georgetown University during an East Coast swing to promote his increasingly enthusiastic embrace of the environment.

"Successful movements are built on passion, they aren't built on guilt," he said, predicting that environmentalism was reaching a "tipping point" where it will move into the mainstream.

"I don't know when the tipping point occurs, but I know where — in California," he said.

Schwarzenegger likened environmentalism to bodybuilding, his first arena of success, which he said was once considered a marginal sport for weirdos.

"It became mainstream, it became sexy, attractive, and this is exactly what has to happen with the environmental movement," he said.

Schwarzenegger appeared at a conference sponsored by Newsweek magazine which put him on its current cover balancing a globe on his finger with the caption "Save the Planet — Or Else."

A blowup of the cover was behind him as he spoke Wednesday. Even Schwarzenegger — whose environmental record isn't as spotless as he sometimes portrays — expressed some amazement about that.

When he ran for governor in 2003, he recalled, he was hounded by environmentalists complaining about his personal fleet of gas-guzzling Hummers.

Schwarzenegger's biggest claim to environmental fame lies in California's landmark global warming law that he signed last year. It imposed the country's first statewide cap on emissions of the heat-trapping gases that are blamed for global warming. The law requires California to reduce emissions by an estimated 25 percent by 2020 — an estimated 174 million metric tons.

Some Democrats in Congress including California Sen. Barbara Boxer, who chairs the environment committee, want to use California's law as a model as Congress aims to write federal global warming legislation.

Schwarzenegger acknowledged California's measure won't alone have a significant impact on carbon emissions. But he said it would serve to push the rest of the country, and the world, in the direction the most populous state is moving.

"California is big, California is powerful, and what we do in California has unbelievable impacts, and it has consequences," he said.

Schwarzenegger didn't mention that before signing the state's landmark bill he sought to weaken it in favor of business interests and threatened a veto if Democrats didn't cede to his requests. He says those changes were merely a difference of opinion with legislative Democrats over how the goals could be achieved.

Schwarzenegger has been making frequent public appearances outside California of late, by his own account aiming to influence the presidential campaign with his own views on politics and the environment. He is not eligible to run for president because he is not a U.S. citizen.

Schwarzenegger travels to New York Wednesday night for dinner with Gov. Elliot Spitzer and for a fundraiser. He was set to deliver an environmental speech at the Council on Foreign Relations in Manhattan on Thursday.