Peter Bergen is CNN's national security analyst, a vice president at New America and a professor of practice at Arizona State University. He has reported from Afghanistan since 1993. The views expressed in this commentary belong solely to the author. View more opinion at CNN.

(CNN)Ten years ago, a rocket landed on a building in Misrata, Libya, killing Tim Hetherington and Chris Hondros, both leading war photographers who were covering the Libyan revolution. Tim was a friend to many, including me. He brought an artist's sensibility to his images of war, like Robert Capa, Don McCullin and James Nachtwey. Tim had recently been nominated for an Oscar for "Restrepo," one of the greatest war films ever made.

After he was killed, Tim's life was documented by the writer Sebastian Junger in the 2013 HBO film, "Which Way is the Frontline From Here?" and a biography, "Here I Am," was published the same year. Tim's work has continued to be exhibited around the world, including at the National Portrait Gallery in Washington, DC.\

The day after Tim's death, I wrote this for CNN:

The first words that were used to describe Tim by almost anybody who knew him were "humble" and "modest."

Yet, Tim was a guy who had great talents. He took highly artistic photos and had released a photography book, "Infidel," which consists of his portraits of American soldiers fighting in the Afghan War.

He was also someone who would go out in the field and take the grittiest pictures of combat.\

For one of those photographs, he won the World Press Photo award in 2007. The photo showed an exhausted, battle-weary GI resting in a bunker in northern Afghanistan, an apt metaphor for what was then fast becoming the longest war in American history.

An image of Tim Hetherington from the HBO film, "Which Way is the Frontline From Here."

Tim had also gone to Oxford to study literature, something he never mentioned in the long days we spent talking and working together on stories for CNN while embedded with a group of Marines in southern Afghanistan in September 2009.

The Marine base in Nawa, Helmand province, was the kind of place that had no water or electricity, and where large barrels of human feces were burned off on a daily basis.

Tim loved it and his enthusiasm for the Marines and for Afghanistan in general was infectious.

Tim was a lot of fun to be around; a mensch, that not-completely-translatable Yiddish word that means someone people find to be an admirable man; someone they want to be around.

Then there was "Restrepo," the film Tim codirected and coproduced with the author Sebastian Junger. Tim worked for more than a year shooting the film, flying back and forth from his apartment in Brooklyn to spend months in the Korengal Valley, then pretty much the most dangerous place in Afghanistan.

At one point during an intense firefight, Tim fell and broke his leg and had to be medevaced out. Yet, he soldiered on to complete the film.

"Restrepo" was a labor of love for Tim. He had a great deal of empathy for the young soldiers he documented. The resulting film is not only the best documentary about war I have ever seen, it is simply one of the greatest of all war films, sharing the epic quality of movies such as "Apocalypse Now" or "Full Metal Jacket."

It is also very beautifully shot, revealing Tim's great sense of picture composition.

"Restrepo" took no strong position on the Afghan War. When Tim screened it for audiences nationwide, he made it clear that he did not want the film to be seen as either an indictment or a celebration of the Afghan war, but more about what war does to small units of men.

And he wanted American audiences to have a more informed discussion of what this particular war was doing to its soldiers.

The approach made "Restrepo" so universal, it could have been made in Vietnam or World War II or in any other conflict where men kill other men; some die, some are wounded and others survive.

When Tim was nominated for an Oscar for "Restrepo" earlier this year, he was "completely delighted," as he put it in an email to me.

In the end, he didn't win the Oscar, but he wrote me afterward saying something that says a lot about Tim Hetherington: "While we didn't get to take home the little gold man, going down the red carpet with those soldiers (from the film) was one of the highlights of my life so far ... and a real finale to an incredible journey. And although this particular journey may be over, the film lives on!"

Tim lived and worked in the toughest environments in the world from, Liberia to Afghanistan, to Libya, where he died while chronicling violence in the war-torn city of Misrata.

But he was never jaded by those experiences, nor was he a showboat about his many years on the front lines.

He was a very gentle man. A gentleman.