An unusual departure for beloved Japanese animator Hayao Miyazaki

The busiest moment in the history of Twitter happened in August when multitudes of Japanese users tweeted the word "balus" while watching a TV broadcast of director Hayao Miyazaki's 1986 animated movie, "Castle in the Sky."

In an indicator of Miyazaki's cultural influence in his high-tech homeland, the made up word, which translates roughly as "destruction," garnered more tweets per second (143,199) than such buzzed about events as the birth of Prince William's son.

Tellingly, the soft-spoken, white-haired grandfather whose work inspired this social media frenzy doesn't use a cellphone or the Internet — "It's jarring and interrupts," Miyazaki said — and he has practiced his craft for the last 50 years, wielding that most old-fashioned of tools, a pencil.

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Now, as the world around him moves ever faster, Miyazaki has announced plans to slow down. The 72-year-old director says his latest film, "The Wind Rises," will be his last.

"Everybody is younger than me," he said, speaking by phone recently from his Tokyo studio through a translator. "They don't understand what it's like to be old. I've learned a lot of things by being 72, and what I've learned is that I don't have a lot of time."

"The Wind Rises," which opened in Los Angeles on Friday for a one-week Oscar qualifying run in advance of a wider release next year, is a departure for Miyazaki. Normally, his family-friendly fantasies such as "Howl's Moving Castle," "My Neighbor Totoro" and Oscar winner "Spirited Away" are set in magical realms populated by wizards, witches and sprites. They're often subtle paeans for pacifism and odes to nature built around strong and clever female characters.

"The Wind Rises," by contrast, is set in pre-World War II Japan and tells the story of a real man, Jiro Horikoshi, who designed the Zero fighter plane. The film, which is based on a short story by Japanese poet Hori Tatsuo, depicts an era when Japan faced some of the same problems that have plagued the country in recent years, including a devastating earthquake and economic stagnation.

Miyazaki had just finished storyboarding a sequence of Japan's 1923 earthquake, which set Tokyo afire, when the powerful 2011 temblor hit.

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"I worked on sci-fi material before, imagining what would happen in the future, but when the earthquake happened two years ago, I felt, 'Oh no, the actual reality of the world has caught up with me,'" he said. "When we could see the changes of the times, I didn't feel I could make some fun fantasy."

Miyazaki, whose father made rudders for the Zero planes, also shows the artistry that went into building the elegant but deadly aircraft, scores of which would ultimately end up attacking Pearl Harbor.

It's an unusual choice of material for a self-identified pacifist, who stayed home from the Oscars when he won for "Spirited Away," because, as he later told a Times reporter, "I didn't want to visit a country that was bombing Iraq."

"Jiro Horikoshi is also a pacifist," Miyazaki said, explaining this seeming contradiction. "Because of the times he was living in, the only thing he was allowed to make was a fighter airplane. I can't accuse my father or Horikoshi of doing the wrong thing when they had to live in such dangerous times."

In Japan, where "The Wind Rises" opened in July, Miyazaki has taken his antiwar stance beyond the cinema. In June, he penned an essay objecting to the new prime minister's plan to amend the country's constitution allowing for the building of a full-fledged military. Some conservatives labeled him "anti-Japanese" and a "traitor."

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The sharp response surprised him. "I feel that there is something of a smell of war," Miyazaki said. "I'm appalled at the outdated nationalism."

The set-to is all the more remarkable given Miyazaki's revered stature in his home country.

Years ago, John Lasseter was walking with the director near his studio in Tokyo when a group of schoolgirls saw Miyazaki and approached him. With his shock of white hair and broad smile, Miyazaki is instantly recognized there — Lasseter likens the director to one of his best-known characters, a grinning, cat-shaped bus from "My Neighbor Totoro."

"He's got the smile that is infectious. His cheeks rise up into his eyes," said Lasseter, the chief creative officer of Disney and Pixar Animation Studios and a longtime friend and admirer of Miyazaki's. "He's so unassuming."