Why No war can be Truly Just

The typical human nature in a war is to survive and reduce the opposition to smithereens, this may seem logical, making it a just war, though every war needs to have casualties, soldiers, civilians, anyone. In a just war, one of the conditions is to make every effort to avoid civilians, though in every war that has been fought, quite a few civilians have been casualties of a so called “just war”, in most cases civilians have been casualties of the oppositions on purpose, for example, WW2, Hitler, the Holocaust, he killed 6 million Jews, they were civilians, and why? Because he did not like them? He made no effort to avoid them, he was aiming for them. Another Example of this is the Vietnam war, USA, during the “Search and Destroy mission”, they used Napalm, this was a chemical weapons that would stick to clothes and skin then burn the victim alive, this was Widley used in flamethrowers to uncover any hiding Vietcong Soldiers hiding in soldiers, later in the war it was used in B-52 Bombers carrying Napalm bombs to drop in Vietcong villages to, again, uncover any Vietcong soldiers, hiding in civilian huts. There are 2 things wrong with what the US did, not only did they use chemical weapons which is not part of the just war conditions, but they made no obvious effort to avoid the civilians, they just dropped napalm bombs directly on their heads. People may disagree with me for the fact that the conditions are not all impossible to achieve, they just have to pay more attention to what they are doing, instead of solely focusing on killing your opposing, and not considering their surrounding and killing innocent civilians. In conclusion, I believe that a just war is not possible to achieve with current human nature by focusing solely on killing the opposition , though people may disagree with me for whatever reason, though this is what I believe to be right.