Nineteen-year-old Lance Cpl. Tyler Underwood is like a lot of Marines.

He's young. He's been in the Corps a relatively short time — two years. He's going to Afghanistan. And he's happy to be doing so.

"I've been in training for it, so I'm pretty much ready. I'm excited," said the Hawai'i Marine and radio operator with the 3rd Battalion, 3rd Marine Regiment.

The West Virginia man and 1,000 other Kāne'ohe Bay Marines packed up and left recently to take on militants and try to build up Afghan governance in southern Helmand province — a daunting task in a country where corruption is rampant and the terrain has flummoxed foreign armies for generations.

In its makeup — and many within the service also say character — the Marine Corps is different. More than any of the four Defense Department services, Marines are young.

According to a study this year by the National Academy of Sciences, nearly 73 percent of enlisted Marines are 24 or younger — far more than the Army, with about 51 percent in that age bracket; or the Navy, with 52 percent; or Air Force, with 42 percent.

'A SPECIAL BURDEN'

At a time when the U.S. has been at war in Afghanistan for nine years and in Iraq for seven with an all-volunteer force, the age demographic has meant unique challenges in the face of repeat deployments, experts say.

"I would say that the young (Marines) have a special burden, which is, they are going from their mommy and daddy's home into conflict — just think about that," said Dr. Judith Broder, a California psychiatrist who treats Iraq and Afghanistan veterans. "And then most of them, if they survive, are coming home to their mommy and daddy's homes."

Broder in 2004 started the Soldiers Project, a nonprofit network of volunteer mental health professionals that provides free counseling and support to Iraq and Afghanistan veterans.

The Soldiers Project operates in California, Washington, Illinois, New York, Massachusetts and is expanding into Hawai'i.

Younger service members who go through combat, or repeat combat, are more likely to experience relationship breakups back at home, use drugs and alcohol, get into bar fights and drive their cars or motorcycles too fast, Broder said.

"It's sort of like what teenagers do, times 10," Broder said.

Todd Bowers, a Marine Corps reservist and deputy executive director of Iraq and Afghanistan Veterans of America, said what young combat Marines need — and what they are increasingly getting — is what he calls "life coaching."

"It does get very overwhelming for these young guys," Bowers said. "I wouldn't necessarily say they are more susceptible (to combat stress), but they haven't had the institutional knowledge and base created to deal with a lot of these things."

YOUNG AND RECKLESS

The younger Marines haven't had to balance budgets or review leases "or work out the little pieces of life," said Bowers, 30, who served twice in Iraq and got back from Afghani-stan in December.

For the majority of the Afghanistan deployment, he was in Farah province where he was assigned to the 2nd Battalion, 3rd Marine Regiment out of Kāne'ohe Bay.

In Hawai'i, military commands repeatedly have stressed the need for motorcycle safety because of the frequency of accidents involving service members.

Younger combat Marines returning home have a combination of a need to replace the adrenaline high of a combat zone, few bills or family responsibilities, and a fat bank account from serving in Iraq or Afghanistan.

Bowers said proper financial management would mean hanging on to the money to perhaps one day buy a house. Not all Marines do that.

"They come back home, and they are like, 'Of course I'm going to buy a Ducati (motorcycle) and blow all my money on this thing,' " Bowers said. "They are 20 years old. That's what you do."

Bowers also knows the stress of combat. In Iraq, the top of his rifle was hit by a sniper's bullet, sending fragments into his face.

'LIFE COACHING'

The organization he now works for, the IAVA, was founded in 2004 by current Executive Director Paul Rieckhoff and fellow Iraq and Afghanistan veterans.

IAVA, with offices in New York and Washington D.C., says on its website that it "addresses critical issues facing new veterans and their families, including mental health injuries, a stretched VA system, inadequate health care for female veterans, and GI Bill educational benefits."

Bowers said the Marine Corps has a fairly strict age cutoff at about 30 to join, and that's one of the reasons the Corps' age demographic is skewed to younger service members.

According to figures provided by the Marines, of 201,473 individuals on active duty, 40 percent are low-ranking privates and lance corporals, and 34 percent are junior-grade non-commissioned officers including sergeants.

Approximately 57 percent, or 115,000 in the ranks, have served less than four years. Only about 3.1 percent are currently at 20 or more years in the Corps.

The Corps' Manpower and Reserve Affairs command in Quantico, Va. said late last week that it would need more time to respond to questions about its demographic makeup.

The command of the Hawai'i-based 3rd Battalion, 3rd Marines, which just left for Afghanistan, said about a third of the unit has been in a war zone before, and two-thirds haven't.

The Marines pride themselves on making do with less, and the service's recruitment pitch is more about the challenge than the promise of benefits, Bowers said.

"The Marine Corps says, 'What makes you good enough to be a Marine?' " Bowers said. "... The old Marine Corps recruitment poster I think said it best when it said, 'We're not going to promise you a rose garden.' But it still draws people in when you see these 18-, 19-year-olds coming out of high school."

Bowers said some Marines decide to leave the Corps after their first four-year term because multiple deployments and training make for an exhausting physical strain.

"I think reality hits people and they go, 'Wow, this is going to be tough,' " he said. "I'm not sure if I can do this for another 16 years." Some also then rejoin after getting out, he said.

Bowers said the Corps is doing a better job of providing the "life coaching" that he talks about.

He was part of the initial 2003 invasion of Iraq, and when he got back, he says he "kind of got a slap on the rear and went on his way."

On his deployment to Afghanistan, which ended in December, there were programs on financial management, and suicide prevention training, he said.

"They are on the right track," Bowers said. "It's just like anything else, it takes so much time."