After a five-year break, Japanese animation legend and "Spirited Away" director Hayao Miyazaki is back with a new film -- and it's already stirring passions, though not for the usual reasons. "The Wind Rises," which opened July 20 in Japan, is a fictional take on the life of Jiro Horikoshi, the man who designed the famed Japanese "Zero" fighter planes used in World War II.

Not only is the real-life subject a departure for Mr. Miyazaki and his Studio Ghibli, which is known for animated movies like "My Neighbor Totoro," about a giant, cuddly, supernatural animal -- the movie's focus on the Zero, which was used in kamikaze operations and the attack on Pearl Harbor, appeared risky to many. That's particularly the case now, amid rising tensions between Japan and neighboring nations over a range of issues from territorial disputes to recent comments by politicians -- including Prime Minister Shinzo Abe -- that appear to downplay Japan's aggressions during World War II.

"My wife and my staff would ask me, 'Why make a story about a man who made weapons of war?'" said Mr. Miyazaki, in a 2011 interview with Cut Magazine. "And I thought they were right. But one day, I heard that Horikoshi had once murmured, 'All I wanted to do was to make something beautiful.' And then I knew I'd found my subject."

Born in 1941, 11 months before Pearl Harbor, Mr. Miyazaki spent his childhood drawing war planes. His love for military craft and aviation is visible throughout his films, from the dragonfly-shaped flying machines in "Laputa: Castle in the Sky" to the amphibious fighter planes of "Porco Rosso." Even his studio, "Ghibli," was named for an Italian scouting aircraft used in World War II.

In "The Wind Rises," Mr. Miyazaki said that he wanted to portray the engineer's life, without being judgmental. "Jiro Horikoshi was the most gifted man of his time, in Japan," Mr. Miyazaki said in the Cut interview. "He wasn't thinking about weapons. Ultimately, he made high-tech destroyers, but really all he desired was to make exquisite planes."

Reactions so far have spanned the gamut. "It's a movie that makes you want to say, 'I've never seen a movie and never will ever see a movie that was as good this one,'" tweeted Mamoru Hosoda, an acclaimed Japanese animator, and director of "Summer Wars".

Other viewers were highly critical. "I've lost faith in him -- can't believe that he would draw a man who built killing machines," said one comment on the YouTube trailer for "The Wind Rises." "The people who built the Zero were Koreans and Chinese who were forced into labor," commented another YouTube user.

Some ordinary viewers complained on the movie's Yahoo Japan site about the piece's graver tone compared to other Studio Ghibli works, and its somber plot, where Jiro Horikoshi's story is intertwined with another about a young female artist struggling with tuberculosis. Parents raised concerns on Yahoo about whether the movie could hold children's attention spans, as well as its emotional accessibility for those who had not been through the war.

Some young people say the film speaks to them, despite its 1930s theme. "I was so tired of being told that children can't do anything," said one 15-year-old girl who posted a comment on Studio Ghibli's website. "Then, 'The Wind Rises' showed me a man who had lived in a much more difficult time, but had been true to his dream and to the woman that he loved. This movie taught me how to live."

"The Wind Rises" has been chosen to compete for the Golden Lion award for best picture at the 70th Venice International Film Festival in Italy, which will be held from August 28th through September 7th. The film opens with Paul Valéry's poem, "The Graveyard by the Sea", which reads, "Le vent se lève, il faut tenter de vivre!" or, "The wind is rising!... We must try to live!"