The double dose of American movie hits known as “Barbenheimer” is fueling a social-media backlash in Japan, the only country to have experienced nuclear-weapon attacks.

The meme combining Oppenheimer, a biography of the inventor of the atomic bomb, and Barbie, a comedy about the fashion doll, had already been trending on X, formerly known as Twitter. Japanese users, who were already embracing the “#NoBarbenheimer” hashtag, were provoked further when the U.S. account for the Barbie film chimed in with a post saying: “It’s going to be a summer to remember.”

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Aug. 6 and 9 will mark 78 years since the bombs were dropped on Hiroshima and Nagasaki. The island nation marks the anniversary with solemn ceremonies and calls to eliminate nuclear weapons. Although Christopher Nolan’s Oppenheimer hasn’t been banned in Japan, it doesn’t have a release date yet after debuting in U.S. theaters last month.

Posts in Japanese described the “Barbenheimer” meme as “terrible” and criticized images combining mushroom clouds and actors from the Barbie movie. Some posted scenes from movies depicting the devastating effects of the bombs.

The uproar forced the Japan office of Warner Brothers, the distributor of Barbie, to respond.

It’s “highly regrettable” that the U.S.-based account for the film engaged with the “Barbenheimer” movement in an inappropriate manner, Warner Bros. Japan LLC said in a statement posted on the official Japanese account for Barbie. The firm said it’s not connected with the meme or the movement, and that it is seeking “an appropriate response” from its U.S. parent.

“Hollywood takes into consideration themes and expressions that are sensitive to certain countries,” said Takashi Uchiyama, cultural and creative studies professor at Aoyama Gakuin University. “I think there was a desire to shift the timing of the release.”

Barbie and Oppenheimer opened on the same weekend in the U.S., leading to a phenomenon where audiences watch the two films in one cinema visit. It’s common for Hollywood films to be released later in Japan after the U.S. premiere. Barbie will debut in Japan Aug. 11.

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An official from Toho-Towa Co., which usually distributes films from Universal Pictures, said Oppenheimer’s release in Japan is yet to be determined. The decision will be made by Universal Pictures, the official added. 

“If Warner Brothers’ American office takes this issue seriously and apologizes, it will probably cause most of this backlash to die down,” said Jeffrey J. Hall, a lecturer at Kanda University of International Studies. “Oppenheimer is likely to receive awards and when that happens we can expect a wide release at theaters in Japan.”

—With assistance from Daiki MAI and Sohee Kim.