I would add another perspective on top. Not only does sound money hinder wars, as you correctly assumed in my opinion, but the border of the monetary system is even the first place where the next war could start. Wars are not only made harder with hard money; rather, it's based on the monetary system's structure and how much power it provides to fight against another monetary system.

As we are all moving towards hyperbitcoinization, we have a monetary system without borders, where the next war could potentially unfold. There is no other monetary system that is "weaker."