Silly Devil's Advocate argument:
What if there are no human soldiers or fighters at all? No-one needs to die in a war again, but wars are won by the side with the stronger tech.
What are the possible outcomes of this? Technologically superior countries start a race to acquire more territory, so large blocks expand and absorb other countries? More wars? Fewer wars? More suffering? Less suffering?
Disclaimer: I'm not imagining this is really possible. As long as some humans from group A don't want to be under the rule of group B, humans will resist and fight. But it is just a thought experiement.
All war tends toward total war, so that will never happen no. The incentive to break any such agreements is too strong.
Philip K Dick wrote a short story similar to this, "The Defenders".
> What if there are no human soldiers or fighters at all? No-one needs to die in a war again, but wars are won by the side with the stronger tech.
Ultimately, the side with more arms will be killing humans, soldiers and citizens of the other side. They simply wont stop at destruction of machines.
Look at Iran war - USA can bomb them without threatening themselves. Or Lebanon - Israel can bomb them with no repercussions. In both cases, weaker side has people killed. In the second one, in an astonishing rate.
I mean if a technological superior country start a race for more territory, we will have another world war and nuclear weapons fired. No robots matter in that scenario.
It becomes nearly impossible for citizens to overthrow dictatorships, and countries with weak democracies will quickly be overpowered by the oligarchs living there, who can now impose their will on the larger population of poor citizens with impunity without worrying about being overthrown by overwhelming numbers. Having an electorate that is so misinformed that it can elect Trump becomes a much more dangerous liability.