On a morning in late July, LZ Gator, Lee Strunk, and Dave Jensen got in a fistfight over a missing jackknife while out on patrol. It was a vicious fight, and Dave Jensen was bigger and stronger than the others. He pinned down Strunk and kept punching him in the nose until it made a snapping sound, but this didn't stop Jensen. It took three people to pull Jensen off. Afterward, Strunk had to be helicoptered to the hospital and rejoined two days later wearing a metal splint on his face.
O'Brien is recalling this story. The fight breaks out over an innocuous thing, but the tension of war heightens everything and amplifies any animosity between the men that already existed. There is no punishment for Jensen; Strunk arrives two days later with little fanfare.
O'Brien says that perhaps in any other place it would have ended there, but because this was Vietnam where everyone had a gun, Dave Jensen became paranoid that Strunk would get his revenge. Strunk had made no claims about wanting revenge, but there was a silent animosity. Jensen kept track of Strunk, he dug his foxhole away from the others, kept his back covered, avoided being alone with Strunk.
The fact that they're at war means that Jensen is conditioned to expect retaliation, and not in a mild sense, but a fatal one. Jensen's suspicions of Strunk overtake him, and he starts changing his behaviors to stay away from him.
After a week, Jensen "couldn't relax" – he said it was like "fighting two different wars." He could no longer sleep well at night, feeling that he always had to be on watch. The line between good and bad guy blurred. Even when there was nothing going on, Jensen sat stiffly against a wall with his weapon at the ready, watching Strunk.
Jensen is coming closer and closer to losing it, and he can't tell who is good or bad anymore. He can't feel at peace or relaxed when the "enemy" isn't shooting at them, because now he sees Strunk as an enemy too. Note that Jensen's feelings here are just a heightened sense of what they all feel, all the time. Death in war can always come at any time, from anywhere.
One afternoon, Jensen finally snapped and started firing his gun into the air while yelling Strunk's name. He didn't stop until he was out of ammunition. Everyone was on the ground, too afraid to go near Jensen. He started to reload, but then sat down suddenly and rested his head on his arms for hours without moving. O'Brien notes that wasn't the bizarre part. Later that night, Jensen borrowed a pistol and smashed it into his own face, breaking his own nose with it.
When Jensen finally does snap, everyone is terrified. He can't kill Strunk, he has no one to target, so he uses the only weapon he has and shoots into the sky because he can shoot nowhere else. He doesn't want to harm anyone. Later, Jensen breaks his own nose in what he sees as the moral equivalent to what he did to Strunk.
With a broken nose, Jensen approached Strunk's foxhole and showed him the damage, asking him if they were even. Strunk nodded.
Out of fear of Strunk's retribution and perhaps some guilt, Jensen gets the OK from Strunk that they're even.
In the morning, Strunk kept laughing. He said, "The man's crazy…I stole his fucking jackknife."
Strunk really did steal Jensen's jackknife, meaning Jensen was justified all along, at least in Strunk's mind. But war turns all of that sort of right and wrong inside out. Jensen and Strunk become in this story symbols for the two sides of the war in Vietnam, each of which has done awful things to the other, and which are now circling around each other in a never ending cycle. What Jensen did, and what was not possible in the larger war, was to find a way to end the cycle.