Ken Burns has just started editing "The War," a 14-hour epic about World War II in seven parts that PBS plans to air in 2007. He's also working on "America's Best Idea: Our National Parks," which is scheduled for release in 2009.

Q. The late historian Stephen Ambrose said, "More Americans get their history from Ken Burns than any other source." What makes your work so popular?

A. I think that the word "history," when you say it to most people, it's homework. To me, the word "history" is mostly made up of the word "story." If there is an explanation for why the films are so successful, it's that we're telling stories, which is how human beings at their essence relate to one another.

I also think that we're interested in not just excavating the dry bones, the pottery shards of the past, but are interested in pursuing a deeply emotional story that reminds people, without kind of consciously engaging any politics or contemporary commentary, imbues people with a present. Paradoxically, by understanding the past you have a sense of where you are, too.

Q. Because many of your documentaries deal with subjects before the invention of movie film and video, much of your work utilizes old paintings and photographs. How will future filmmakers use e-mail letters, digital photos, YouTube videos and other electronic data?

A. A lot of stuff will be lost in the ether. There will be too much stuff and not enough. Just as there is, in the past, not enough stuff. Here, there will be too much and not enough, because you'll be almost drowned under a tsunami of choice. But at the same time, sometimes those things that we can count on, say a diary from the 19th century, even if there's an e-mail trail, it might not be accessible. It might not be retrievable. We may be on such different systems that it may be impossible to read information that we made in the '70s and '80s.

I think it provides all of us storytellers with daunting challenges. Basically, you have to work with the tools that you have, whatever they may be, to try and tell a story.

Q. What is the best documentary you've ever done?

A. Up until now, I've steadfastly, like a good parent, said, "I love them all the same," and that's still true. Another way of doing it is, when I was working on the jazz film a few years ago, Duke Ellington was once asked what was his most important composition. He said, "The one I'm working on now."

Q. What will capture the imagination and attention of documentary storytellers a century from now? How will they interpret the impact of 9-11?

A. I'm finishing the biggest work of my life right now on the Second World War. Of course, that has as its sort of signal moment, Dec. 7, 1941. I think Sept. 11 will be kind of that all-encompassing date that everything that came before it is before and everything after it is after.

As we look back on the first Gulf War and the second Gulf War, we might be saying that this was the period of the petroleum wars. We might have a perspective and an honesty and a self-critical ability to say, "Perhaps that's what this whole thing was about." We hopefully will be looking back from a position of having not ruined ourselves with it, as so many other great empires have done out of hubris and arrogance.

Q. Give us a sneak preview of "The War" series.

A. It's a bottom-up look at the American experience in the Second World War. We don't have any experts in the films. They're all people who lived through it, about 40 of them. They are so-called ordinary people whose tales are interwoven, kind of like a complicated Russian novel. The intertwining of these ordinary lives allows us to not be distracted by celebrity, which is the new replacement for the great men theory of everything.

In point of fact, in all wars, it's the privates that do the fighting and the dying. So we have ball turret gunners in B-17s and grunts landing at Omaha Beach and Marines landing on a whole host of Pacific islands and the pilots and the nurses and Navy men and you name it. We spend about 20 percent of the film in the homefront and the other 80 divided horrifically between the European and the Pacific theaters.

This is no longer the good war of our imagination and subsequent public relations, but in fact the worst war that ever happened. It happened to be unambiguous in its size and in its raison d'etre. But everything else about it was the worst of all possible wars. We have not blinked or flinched from showing that.