An infantryman with the 3rd Infantry Division crosses farmland during a foot patrol near Forward Operating Base Shank, Logar province, Afghanistan, Oct. 10, 2013.

CAMP LEJEUNE, N.C. — Mike Compton is one of America's elite warriors, except he no longer has a war.

"It feels great," he says, "almost like a drug you don't want to give up."

"Home for me was Afghanistan in the middle of a firefight," says the 29-year-old married father of two, echoing sentiments of other special "operators" who achieved a hard-earned place at the tip of America's fighting spear.

With American combat over in Iraq and U.S. troops leaving Afghanistan next year, surveys show a war-weary public eager for 12 years of fighting to go away.

But for a core group in uniform who spent their adult lives in endless cycles of training and battle, who — military psychiatrists say — are now better adapted emotionally to combat than being at home, re-adjustment to a life of peace will be challenging.

They are among an estimated 1.2 million service members who will begin transitioning out of the military in the next four years as combat ends and the military is downsized.

"It's almost like an existential crisis," says Delight Thompson, a neuropsychologist who treats members of the Marine Special Operations Command here. The unit is where Compton earned respect in 2009 for going back into battle even after suffering a brain-jarring head wound from gunfire in Afghanistan.

"You're having to kind of find yourself again," Thompson says about war winding down for these troops, "develop this new identity. And a key part of that is finding what your new purpose is in life."

Charles Hoge, a retired Army colonel, psychiatrist and author of landmark studies on combat stress, believes that the vast majority of these veterans — and he has seen many like Compton — will make that crucial adjustment and find their way.

But it is not something that can be easily predicted in every case.

Compton suffered brain injury, post-traumatic stress disorder, torn ligaments, herniated discs and arthritic joints. Home now with his wife, Abby, and two young sons — Christopher, 2 and six-month old Nicholas — he awaits a fitness determination fearing the worst: a medical discharge or retirement at age 30.

It will mean, he says, "putting down that rifle and picking up something else."

But Compton concedes that he is without a plan for his future , apart from a few drifting thoughts about security training, perhaps for educators following tragic mass shootings in classrooms.

He has yet to forge a pathway for himself out of war.

In Afghanistan, Compton was part of Marine special operations team of 15 who trained local militia and attacked Taliban strongholds near the border with Turkmenistan. In a long battle through the riverside hamlet of Daneh Pasab in March 2010, Marine and Army commandos killed four dozen enemy fighters.

Back home on a cul-de-sac north of Camp Lejeune, Abby hounds him for not taking out the trash.

"You come home, and all of a sudden everything you did, it's not normal anymore," Compton says with a note of bitterness. "They wanted these high-functioning killing machines. Well, guess what? You got it. Now we got to re-integrate back into society."

Among those facing this adjustment are the secretive commandos whose exploits — the killing of Osama bin Laden, the rescue from pirates of cargo ship Capt. Richard Phillips and, recently, raids in Africa to seize terrorist leaders — have fired the public imagination.

While combat for these Navy SEALs; Army Delta Force commandos, Rangers and Green Berets; and Marine and Air Force special forces continues, the doorway to a relentless pace of back-to-back missions is closing.

"What we're seeing now is just the beginnings of a wave that's going to be coming at us as we start winding down combat operations," says Marine Col. Michael Sweeny, head of a special operations program aimed at helping troops adjust from combat.

"As we transition out of Afghanistan, transition out of war...how much baggage are we still carrying with us?" asks Marine Col. Andrew Milburn, commander of the spec ops regiment. "That transition is not going to be an easy one psychologically for a lot of our guys."

Natural born fighter

This is the story of Marine Staff Sgt. Michael Compton — joining at 19 in 2003, charter member of the Marine Corps' special operations regiment formed in 2006, five combat tours, two re-enlistments.

Warfare, he says, is "what I was put on this earth to do." Leaders say he excelled among the bearded fraternity who meet exacting standards, are equipped with the finest battle gear and conduct the most sensitive missions.

"He's one of those guys...an operator through and through," says Master Gunnery Sgt. Frank Mercer, operations chief for the unit Compton served in during a 2009-10 deployment. "We're very fortunate in this world right now to have very intellectually sound individuals who can make split-second decisions under a lot of pressure."

But there is a physical and emotional cost for service during a decade of war.

Compton is not at all certain what path he will take after the military. The university setting is an option under the new G.I. Bill, but one that seems colorless and dry. Easy choices are security work, perhaps even back in Afghanistan as a private contractor. All pale in comparison to going to war with his team of operators.

Abby, 27, admits she's really worried. "For 11 years, this is all he has done," she says.

But it's also an article of faith for her that Mike is more than just a Marine with a weapon.

"It's not who he is entirely," she says. "He's funny. He's caring. He's outgoing. He's giving. I mean he's a lot of other things than just a bad ass."

Hard to adjust

A paradox of war is that many who are good at it are not so good being away from it, researchers say.

"I never got weirded out going on deployment," Compton says. "It always got weird for me personally when I would go home."

The reason, scientists say, is the human brain's innate adaptability, literally rewiring itself during prolonged periods of combat to survive.

A constant vigilance to threats becomes second nature. Emotions switch off so witnessed horrors don't impede action. Near-death memories are stored in minute detail — after being experienced as if in slow motion — so the brain never forgets.

"Your body has now learned a new normal," says Thompson, who sees these changes in troops she treats, "not just behaviorally, but bio-chemically, structurally, at the cellular level."

It helps make them among the best combat troops the nation produces, says Hoge, They're in fact highly effective in the combat environment."

And they love it.

"It feels great. I'm functioning like I'm supposed to be functioning. I'm taking the fight to the enemy. I'm helping out my guys to my left and my right," Compton says.

Lucky to be alive

On the morning of Dec. 29, 2009, a Taliban bullet tore through Compton's helmet as he was reaching for an ammo can outside a foxhole during a gunfight.

He briefly lost consciousness lying in the foxhole. The round didn't penetrate bone but cut a deep furrow across the top of Compton's skull before burrowing into the inside of his helmet.

In the heat of battle, the trajectory, path and velocity of the nearly fatal round was capricious. A similar head shot killed Compton's team leader — Gunnery Sgt. Robert Gilbert II, 28 — in March 2010.

Compton's brain was rattled, with damage little understood by battlefield doctors then. He shrugged off migraines and vision problems, talked his way back into combat, finished the deployment and returned to Afghanistan with his team yet again in 2011.

"That's the norm," Master Gunnery Sgt. Mercer says of Compton's returning to the fight. "These guys are really dedicated. They're extremely hungry."

Navy Adm. William McRaven, who commands all 66,000 special operations troops, said last year that this kind of dedication also causes countless troops to hide their physical and emotional wounds. "You want them to come forward and...expose their fears to you," he said. "That's not easy to do."

One crucial fear is life away from the team and combat.

"You're on a train that's going 300 miles an hour," Compton says of combat. "Everybody around you is also on that train. The second you get back (home), that train slows down to 15 miles an hour, back to normal speed where everybody else is and you still want to go 300 miles per hour. You're still on that train. You're still on that ride. You want to keep it going."

So the vigilance of war turns into hyper-vigilance — restlessness, avoiding crowds, irritably lashing out. The emotions turned off in combat don't turn back on.

"There were times when he would tell me 'I know I'm supposed to care. I know I'm supposed to love you. I just feel nothing,' " Abby recalls. "This isn't the man I married."

He was in the throes of PTSD, therapists later told him.

"You don't stop being a warrior," says Hoge, author of Once a Warrior, Always a Warrior, a book aimed at helping troops adapt after war. "Your body doesn't stop doing what it's become so adept at doing."

Compton's brain injury had grown worse from repeated exposures to blasts during combat, the migraine so severe he would throw up.

During team assault practices in 2012, Compton would forget which room he had cleared when troops gathered for an after-action review. "I felt inadequate and embarrassed," he says.

He finally began extensive neurological evaluation, therapy and physical rehabilitation earlier this year. He's had arthroscopic surgery on both knees and his right shoulder; and a nerve block injection to ease the headaches.

Weeks of extensive work-up at an advanced brain injury facility in Bethesda, Md., alerted Compton to what could happen if went back to war: "I'm a blast or two away from scrambled eggs," he says.

He and Abby have grown closer since the Bethesda evaluation. "I realize what he's going through are things he can't control," she says.

The family has begun relocating from a home near Camp Lejeune to their hometown of Williamsburg, Va. A future option Compton toys with is advising educators how best to respond if a gunman enters school grounds. "If they knew what to do, how many more lives could they save?" he says.

Maj. Gen. Mark Clark, commander of Marine special operations, pledges to support his troops as the fighting winds down. He worries about public apathy.

"Our country, I love it, but sometimes we're quick to move on...sometimes we forget," he says. "The effects of this conflict are going to continue for decades."

Meanwhile, Compton awaits his fitness report. He could leave the Marines within six months.

"I'm kind of reconciled to the fact that I'll be found unfit," he says. "There's always that secret hope that they'll come back and say, 'Fit for duty.' And you can get back on that train again.

"But that's not really the best call. I know that now, for both myself and my family."

