LOS ANGELES >> For as long as he can remember, Rishi Sharma’s heroes haven’t been sports stars or movie stars or any other kind of stars. They’ve been the U.S. combat veterans who won World War II.

Alarmed that even the youngest of them are now in their 90s and dying each day by the hundreds, the Southern California teenager has launched a campaign to try to ensure each one’s legacy.

“I’m on a mission to in-depth film interview a World War II combat veteran every single day,” the earnest 19-year-old says after a recent afternoon spent in the living room of William R. Hahn of Los Angeles, where Sharma mined the 93-year-old’s memories for hours.

His Canon 70D camera rolling, his long, jet-black hair tied back in a tight ponytail, the son of Indian immigrants listened intently as Hahn recounted how he received the Silver Star for bravery by charging through a hail of gunfire on Easter Sunday 1945 as Allied forces retook the German town of Hettstandt.

Asked if he considers himself a hero, Hahn chuckled.

“Not really,” said the retired metal-shop teacher who had a bullet come so close to him that it blew the canteen on his belt to smithereens. Other guys, he said, did similar things, and not all came back to talk about it.

Sharma wants to meet and honor every one who did, and he knows time is not on his side.

Of the approximately 16 million Americans who served in some capacity during WWII, some 620,000 survive, but they are dying at the rate of nearly 400 a day, according to the National Museum of World War II.

“I want to create this movement where people, where they just realize that we have such a limited time with these men who saved humanity,” he says. “Let’s try to learn as much as we can from them and give them a proper send-off and make them feel like their sacrifices they made were worth it.”

He figures he’s got about 10 years to do that so he’s putting off college, putting off finding a job, putting off looking for a girlfriend, putting off just about everything except occasionally eating and sleeping between interviewing combat veterans.

Since childhood, Sharma says, he’s been fascinated by the sacrifices men his age made during WWII, risking their lives for freedom, then returning home to raise families and take everyday jobs as they transitioned back to civilian life.

He read every book and watched every documentary he could find. But it wasn’t until his junior year at Agoura Hills High School, just north of Los Angeles, that he became committed to meeting them.

He came across the name Lyle Bouck, one of the heroes of Germany’s Battle of the Bulge offensive in Belgium, as he read historian Stephen Ambrose’s book “Citizen Soldiers.”

Fascinated, he looked up Bouck’s phone number and called him, not realizing it was 1 a.m. where the 92-year-old war hero lives. A friendly voice on the other end of the phone told Sharma if he called back at a decent hour, Bouck would be happy to talk.

That’s when the teen had an epiphany. “It made me realize these guys are really out there! And I could do this for all of them.”

Soon Sharma was riding his bike to every retirement home within pedaling distance. After he interviewed every combat-hardened soldier there, he turned to veterans halls, then the internet.

Borrowing his parents’ car, he traveled to Oregon over the summer, then back down the California coast, interviewing still more people. He’s up to about 160, and has plans to expand his travels in the weeks ahead to Arizona and other states and, on next month’s 75th anniversary of the Pearl Harbor attack, to Hawaii.

He makes a DVD of every interview and gives it to the veteran. Some have passed on copies to the World War II museum.

“He’s just totally dedicated and a very decent young fellow,” says Howie Beach of Fullerton, whom Sharma recently interviewed. What he is doing is important, says Beach, another Silver Star recipient who at 91 sometimes speaks to high school groups.

“But a lot of them go on their merry way, just taking their lives and their freedoms and all that for granted,” Beach says of those students. “So it’s good to see a young man like Rishi with such a convincing way about him.”

Such an effort doesn’t come cheap, however, and Sharma quickly exhausted his modest life’s savings carrying it out. He raised about $3,300 through a GoFundMe account and has spent most of that. To economize during the Oregon-Northern California trip, he limited himself to one meal every other day.

But Sharma, who also founded a nonprofit called Heroes of the Second World War, has huge dreams for his effort. He’d like to eventually recruit others to help conduct interviews, perhaps get the interviews to museums and allow others to get to know some of the people he says have become his closest friends.

“This one guy I interviewed in Oregon told me he hadn’t been visited by anyone in over five months and that he was just waiting to die,” Sharma recalled. “This is a 94-year-old who saw combat in the South Pacific, and now he has no one.”