'Titanic' director James Cameron says Jack needed to die

It's been over 20 years since "Titanic" was released, but director James Cameron still has to defend his decision to have Jack Dawson die at the end of the film. 

Cameron told "60 Minutes Australia" in a new interview that Dawson's death was "fundamental" for the romance movie to make sense. 

"It had to have a tragic, bittersweet ending," Cameron said , according to news.com.au.

At the end of the film Leonardo DiCaprio's Jack, freezes to death after he gives up a floating door for love interest Rose, played by Kate Winslet, so that she could ultimately survive. 

"I mean to me a love story is a transfer of energy, sometimes bi-directional," explained Cameron. "In this case it was a transfer of energy from his life force to her."

Cameron went on to share that the door was a symbolic gesture, with Jack essentially giving Rose "that spark she needed to survive" and showing "her another way of living."

“The promise that she would never let go is the promise to never let go of life," noted Cameron.

He continued: "The irony is she had to let go of his hand and let him go, but she never let go of what he had given her, which is that gift and that spark. So yeah Jack had to die, that was kind of fundamental."

Last November, Cameron also addressed the huge question of why Jack wasn't able to live, explaining that along with it being "an artistic choice" the 1997 movie also "would have been meaningless." 

"Very simple. . . . Obviously it was an artistic choice, the thing was just big enough to hold her, and not big enough to hold him . . . I think it’s all kind of silly, really, that we’re having this discussion 20 years later," Cameron told Vanity Fair at the time.

"But it does show that the film was effective in making Jack so endearing to the audience that it hurts them to see him die," added Cameron, noting that, "Had (Jack) lived, the ending of the film would have been meaningless."

"The film is about death and separation; he had to die," explained Cameron. "So whether it was that, or whether a smoke stack fell on him, he was going down. It’s called art, things happen for artistic reasons, not for physics reasons."