The war was a psychological war. The allied soldiers (America, Australia, New Zealand, South Korea, South Vietnam, Thailand and Philippines) had to fight against unknown enemies. Men, women, children, any one could have been an enemy, so they had to decided whether to kill people before they killed them, etc. So they killed innocent people, hoping they weren't. Also the chemical warfare had terrible outcomes on the soldiers, and sometimes their children (in the case of Agent Orange). It led to all sorts of defects amongst the people and led to large numbers of diseases in children. For example, children born without limbs, high numbers of children with Downs syndrome born, and other genetic defects.
Thousands of america's sons were forced against thier will to fight in a war,which gained nothing,but early death for them ,and ripped holes in families waiting back home