I have known hundreds of Vietnam war veterans and the percentage of those having any trauma is very, very low. I am a veteran of that war myself. I also flew as aircrew in combat in the Second World War and know that most combat veterans experienced few problems. Most people "recover" quite handily and resume their normal life after this war or any catastrophe.
If these claims were true, 43 per cent of the British civilians who survived the horror of the Second World War bombing would still be walking around in a daze. On the contrary, when the war ended, most people put those horrors behind them and resumed their normal lives. My experiences with German civilians have been the same. They resumed their normal lives without great difficulty.