No one tell Chris Christie.

In a new Rolling Stone interview out Thursday, the New Jersey governor’s favorite rock star had some pointed words for Christie’s new boss and the standard-bearer for the Republican Party: Donald Trump.

“The republic is under siege by a moron, basically,” Bruce Springsteen told Rolling Stone. “The whole thing is tragic. Without overstating it, it’s a tragedy for our democracy.”

Springsteen pointed to Trump’s warning that the election results will be “rigged” in Hillary Clinton’s favor and support from white nationalists as proof that he’s “pushing people beyond democratic governance.”

“Once you let those genies out of the bottle, they don’t go back in so easy, if they go back in at all,” he said. “The ideas he’s moving to the mainstream are all very dangerous ideas – white nationalism and the alt-right movement.”

The singer posited that Trump’s “simple answers to very complex problems” related to deindustrialization and globalization have drawn disillusioned American workers to his campaign.

Springsteen has been critical of the real estate mogul since early in the 2016 race, when he called Trump an “embarrassment.”

A number of other major artists have spoken out against Trump and asked him to stop using their music at his campaign events, including Neil Young, Twisted Sister, and R.E.M.