Bradley Cooper plays U.S. Navy SEAL sniper Chris Kyle in "American Sniper.” (Keith Bernstein/AP/Warner Bros. Pictures)

The makers of “American Sniper” said they wanted the movie to be a thoughtful character study of the most lethal military sniper in U.S. history.

But the movie — which shattered January box-office records over the holiday weekend with $105 million in sales — has also inflamed the debate over America’s controversial wars, with one side decrying it as jingoistic propaganda and another defending it just as fiercely as a paean to the country’s underappreciated veterans.

In West Los Angeles, a billboard for the film was vandalized over the weekend with the word “Murder!” written in red spray paint.

The director Michael Moore and the actor Seth Rogen took to social media to air their thoughts, although they both later backtracked. Moore appeared to slam the glorification of sniper Chris Kyle in the film, writing on Twitter: “My uncle killed by sniper in WW2. We were taught snipers were cowards. Will shoot u in the back. Snipers aren’t heroes.” Rogen compared the movie with a Nazi propaganda movie that appears at the end of Quentin Tarantino’s “Inglourious Basterds.”

The backlash — from politicians, veterans and other celebrities — was swift.

Clint Eastwood's new film "American Sniper" has become the latest battleground in the culture wars. Washington Post columnist Alyssa Rosenberg explains why its politics matter. (Jorge Ribas/The Washington Post)

“They aren’t attacking a conservative right of America. They are going after the fabric of America at a time when it is celebrating a hero and when the country needs a hero,” author and former Navy SEAL sniper instructor Brandon Webb said in an interview.

Country singer and veteran Craig Morgan wrote to Rogen on Facebook: “I’m sick and tired of people like you running your mouth when you have no idea what it takes for this country to maintain our freedoms. If you and anyone like you don’t like it, leave.”

Sarah Palin wrote on Facebook: “God bless our troops, especially our snipers.”

The exchanges became the latest flash point to emerge from the country’s divergent assessments of its 13-year military engagement overseas. The movie stirred up a host of questions surrounding the way we treat veterans, whether the wars were worth the immense sacrifice, and how to judge actions taken by soldiers in the heat of battle.

The debate also hints at another gulf in U.S. politics: the plummeting number of Americans who serve in the armed services. Military analysts said that has given rise to a widening cultural divide between civilians and combat veterans. Today, about 0.5 percent of Americans serve in the military, a smaller share than at any other time since World War II.

But the movie’s popularity transcended those differences, said Dan Fellman, head of distribution for Warner Bros., which released the movie.

“Red state, blue state, small town or big city, across the board, the film broke records everywhere and resonated with all audiences,” Fellman said. “Every once in a while, a movie comes along that reaches the core of moviegoers, that resonates emotionally to all audiences.”

In the latest trailer for "American Sniper," directed by Clint Eastwood and based on the autobiography of the name, Bradley Cooper plays U.S. Navy SEAL sniper Chris Kyle, who is said to have had the most confirmed kills in U.S. military history. Kyle struggled with PTSD and was killed at a gun range by a fellow veteran in February 2013. The film opens Dec. 25. (Warner Bros. UK)

The controversy surrounding “American Sniper” wasn’t the key to the film’s initial success, but the heated conversation has created a powerful swirl of interest.

“The movie has become more a film that people want to see because they want to be part of the national conversation around it,” said Phil Contrino, a movie analyst at BoxOffice.com.

Twitter said discussion around the film was more than double the volume of the average for films. The hashtag “#liberalwarmovies” was one of the top trending topics Tuesday, with conservatives mocking left-leaning critics of the movie for being out of touch with and insensitive to the sacrifices of the military. Facebook data showed the film sparked the most active conversations in traditional red states such as West Virginia, Wyoming, Kentucky and Oklahoma.

“American Sniper,” directed by Clint Eastwood and starring Bradley Cooper, is based on the memoir of Navy SEAL Kyle, who wrote about his four tours in Iraq between 2003 and 2009.

Kyle was no ordinary soldier. Before he was shot to death at a Texas gun range in 2013, Kyle claimed he killed at least 150 people while working as a sniper in Iraq. He oozed conviction and charisma. He wore big boots. He spoke with a languid Texas drawl. He wrote a best-selling memoir. He made millions.

And then there were the tales Kyle told about himself, which came under increasing suspicion after numerous journalists tried — and failed — to corroborate them. Among them: Kyle once said he fatally shot two armed Texas thugs who wanted to steal his truck. He said he traveled to New Orleans and killed 30 bad guys in the chaos following Hurricane Katrina. And he also falsely claimed he punched out former Minnesota governor Jesse “the Body” Ventura after Ventura, a former member of a Navy Underwater Demolition Team, disparaged the Navy SEALs.

“There were a lot of things he told people that are really unverifiable,” journalist Michael J. Mooney, who wrote a book on Kyle, told The Washington Post in July.

A war movie for a nation weary from years of conflict, “American Sniper” wasn’t supposed to be a massive hit. It was expected to generate $60 million in revenue in its first weekend of wide release.

But a combination of Warner Bros.’ shrewd marketing campaign, the impeccable timing of the release just days after it received several Oscar nominations and a torrent of social-media recommendations gave it a bigger opening than “The Hobbit” or “Avatar,” movies with much bigger budgets.

Many critics have hailed the film for its rich and humanizing portrayal of a man at war. The movie was nominated for six Oscars, including best film and best leading actor.

Since their initial remarks, Moore and Rogen have said their comments were taken out of context. Moore said he wasn’t directly referring to the film in his comments about snipers.

Rogen said he actually liked the film and wrote a new tweet Monday saying he wasn’t directly comparing “American Sniper” with the propaganda movie in “Inglourious Basterds.” “Big difference between comparing and reminding,” he wrote. “Apples remind me of oranges. Can’t compare them, though.”

Actor Cooper has also tried to calm the debate, saying the film wasn’t intended to be political but a human story about a soldier’s life and internal struggles.

“It’s a movie about a man — a character study. We hope that you can have your eyes opened to the struggle of the soldier rather than the specifics of the war,” Cooper said at a news conference last week in New York.

From the beginning, Warner Bros. has tried to emphasize the human story of Kyle.

Warner Bros. began its marketing blitz in October with the release of a trailer that immediately sparked huge interest online. In it, scenes of Kyle’s family life in the United States are juxtaposed with scenes at war, where the sniper is confronted with difficult decisions to kill targets — even children — for the safety of his troops. The trailer is artful, suspenseful and a clear dive into the psychology and struggles of soldiers at war.

The trailer and subsequent clips of the movie were slowly released on social media. On YouTube, the trailers were seen more than 10 million times combined.

After the film was released, Kyle’s widow, Taya, wrote a guest post on the Facebook page for “American Sniper” that was liked more than 39,000 times.

“I also just want to cry and cry and honestly have today. Thank you for being willing to watch the hard stuff and thank you for hearing, seeing, experiencing the life of our military and first responders,” she wrote.