American Sniper may be on-course to be the biggest grossing war movie of all time, and it may have scored surprise Oscar nominations for Best Picture and Best Actor, but should we really go along with the whole hero narrative? Not according to documentary filmmaker Michael Moore, who has described snipers as "cowards".

American SniperBradley Cooper plays sniper Chris Kyle in Clint Eastwood's American Sniper

Chris Kyle, played by Bradley Cooper, is credited as the deadliest sniper in U.S. military history. He was killed at a Texas shooting range by a former soldier after returning from Iraq in 2013, though his Hollywood story was already in the works. The movie has already set box-office records for a January movie and pulled in an estimated $105 million for the long holiday weekend.

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Still,  Clint Eastwood's movie didn't chime with everyone (for the record, it got mixed reviews from critics) and Moore wasn't having any of the patriotic stuff, tweeting, "My uncle killed by sniper in WW2. We were taught snipers were cowards. Will shoot u in the back. Snipers aren't heroes. And invaders r worse."

Moore was elected to the Academy of Motion Picture Arts & Sciences' Board of Governors in 2010 though lost out on another term in July 2013. Though he wasn't keen on American Sniper, the filmmaker did have high praise for another of the Best Picture nominees.

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"Everybody else - try to see SELMA this weekend! Simply because it is a piece of brilliant filmmaking, the likes of which are so rare..." he tweeted.

Though nominated for the big prize, Selma - based on the 1965 Selma to Montgomery voting rights marches led by Martin Luther King Jr - failed to land Oscar recognition for lead actor David Oyelowo and director Ava DuVernay. 

Watch the American Sniper trailer: