VA study shows that battlefield stress, aging veterans – “all the little petty things — all that Facebook, all that stuff — it doesn’t matter. It doesn’t exist.”

He will talk about the nightmares, vivid images in his mind of the carnage he witnessed after suicide bombers detonated explosives and dozens of civilians died, many of them children he and other Marines rushed in trying to assist.

“(I’m) waking up screaming, fighting, kicking (at) nothing in the dark. It just feels like I’m re-enacting everything that happened,” he says.

Finally, he’ll say he will return to Afghanistan as a civilian contractor, again handling a bomb-sniffing dog — both because the money is good, $105,000 a year before bonuses and overtime, and because life there makes sense.

“It’s a simpler life over there,” he says at the end of the day. “All you’re really worried about is the welfare of yourself and the people around you. And all the little petty things — all that Facebook, all that stuff — it doesn’t matter. It doesn’t exist.”

That he is heading back into the war zone with a body that — if the scientists’ theory is correct — might be aging too quickly, leaves Pierce with a sense of resignation. “I have to agree,” he says. “I have high blood pressure, I hurt all the time, and even if I don’t like to admit it, I am carrying some extra weight.”

For Kendall Pierce, who married her husband last December, these signs of aging seem frightening and unfair. He has already sacrificed so much, she says, something evident any night when she shakes him out of one of his terrible dreams.

“You can see the fear on his face. And, oh my gosh, it’s just heartbreaking,” she says. “He can look at me and realize, ‘OK, I’m at home. I’m with Kendall. I’m OK.’ Some nights, he’ll talk about it. And sometimes, he’ll just sit there and squeeze me with one of those big bear hugs and not let me go…