Though Trump publicly—albeit half-heartedly—asked for Bannon to calm down his campaign against Republican senators last week during a press conference with McConnell, Bannon said he is acting as Trump’s “wingman.” He launched a broadside against George W. Bush, who gave a speech rebuking Trumpian ideology last week. Members of the audience booed at the mention of Bush’s name.

“It’s clear he doesn’t understand what he’s talking about,” Bannon said, “Just like it was when he was president of the United States.”

“There has not been a more destructive presidency than George Bush’s,” Bannon said. The reaction to this line was more muted, with only scattered applause. One Republican strategist who spoke on condition of anonymity because of his involvement in some races in California told me that at his table only three of seven people applauded. “This was a populist speech, this was not a Republican Party speech,” the strategist said. “Nobody in this room had ever heard a speech like this before.”

Bannon tailored his speech to the California audience, warning darkly of the power of Silicon Valley, which he cast as the “beating heart” of the resistance to President Trump.

He even warned that Silicon Valley might engineer a secession attempt, saying that if California Republicans do not roll back the law that has made the state a “sanctuary state” for immigrants, “10 or 15 years from now the folks in Silicon Valley and the progressive left in this state are gonna try to secede from the Union.”

“We don’t have a problem with ideas,” Bannon said of Republicans. “We have a problem with understanding how to win. It is about winning, nothing else matters.”

Bannon has connections in conservative circles in California dating to his years as a film producer and banker in Hollywood. Los Angeles is where he met the late Andrew Breitbart, to whom he lent office space in the early years of Breitbart News.

California politics are dominated by the Democratic party, though the Republicans hold several key congressional seats. Seven of these 14 Republican incumbents’ districts were won by Hillary Clinton in 2016. The last Republican statewide office-holder, former Governor Arnold Schwarzenegger, finished his last term in 2011.

But outside of electoral politics, California has been home to some of the most influential people on the right in recent years, including people like Breitbart, Ann Coulter, and White House domestic policy advisor Stephen Miller, who is close to Bannon. (Miller attended a party for Laura Ingraham’s new book held at the Breitbart “embassy” in Washington on Thursday night, where Bannon hailed him as “the last one behind enemy lines.”)

Apart from Bannon, few big names on the right were in attendance; at one point during his speech, Bannon gave a shoutout to one of them, tax-cut guru Grover Norquist, who is speaking at the convention on Sunday.