A California man allegedly pummeled a fellow restaurant patron who wore a hat with President Donald Trump’s 2016 campaign slogan “Make America Great Again” — written in Russian.

David Delgado, 32, of Winnetka, was arrested around 9 a.m. Tuesday in connection with the incident, which took place Sept. 2 in the restroom at the Tower 12 restaurant in Hermosa Beach, local police Sgt. Robert Higgins told the Daily Breeze.

The victim was inside the bathroom around 6:40 p.m. when Delgado allegedly walked up to him and asked the meaning of the Russian words on his red cap, according to Higgins.

When he explained, Delgado socked the man in the face, knocking him to the floor, Higgins said.

Delgado then grabbed the offending hat and took off, the police official added.

“It’s not clear who insulted who, but the hat is at the center of this whole mess,” Higgins told the Breeze.

Investigators identified Delgado using surveillance video and other evidence, according to the report.

He was busted at his home in the San Fernando Valley and booked on suspicion of robbery and battery with serious injury, the paper reported.

Inmate records indicate he is being held in lieu of $100,000 bail.

Hats with “Make America Great Again” written in Russian are available from Amazon, eBay and other online retailers. The message is likely a reference to investigations into Russian meddling in the 2016 election.