To say you are against rules of war is to say you are for the unprovoked killing of civilians by soldiers of nations foreign to those citizens. Rules are in place for a reason. Just because war is an inevitable part of society, leaving it to destroy society is just irresponsible. Many times, organized killing of civilians in order to achieve victory does not justify itself as a means to an end - strategically, tactically, or ethically.
For example, when Russia went to Afghanistan it slaughtered thousands of Afghans. While on paper this looks good to the war office, in reality that only fueled anti-Soviet sentiment in Afghanistan which produced a strong resistance that ultimately removed Russia from Afghanistan.
The same happened in Vietnam to a lesser extent. While the US did not try to kill civilians, some 2 million innocent Vietnamese died, albeit not just the US's fault. The result was heavy anti-war sentiment and the eventual loss of the Vietnam War, despite the tactical success and superiority the US enjoyed in the war.
The same issues hamper our efforts today in the Middle East. For every civilian we kill, we, more than likely, produce at least one enemy extremist.
Then, your theory that making war worse would make many think twice about starting a war is wrong. Let's use another historical example - the cold war. In theory, if we build enough nuclear weapons, everybody would step down in fear of being crushed by our massive nuclear arsenal. However, what actually happened was that many nations, exclusively Russia, built up their own arsenals to combat ours, and before we knew it the price of war was the extinction of humanity. The repercussions of the cold war still threaten us today. The threat of MAD still remains today.
I really don't think you've thought about this enough to come to such a bold conclusion as "total war" or "no war."
