Why was Lt. Carroll's death different from Jenkin's death

As soon as the soldiers realize that Lieutenant Carroll has been hit, they start shooting with an unbridled vengeance to avenge their fallen leader. The platoon evacuates when the American choppers arrive and spray the town with bullets, killing everyone - civilians and Viet Cong alike. The helicopter carrying Lieutenant Carroll goes straight to the medical clinic at Chu Lai, but nothing can be done. Monaco leads the squad in a prayer for their “fallen angel.” Unlike Carroll, Jenkins steps on a landmine. The men are still shaken up though.