I agree that it is not simple, and that the worst consequences are awful. But unfortunately, opting out is not an option, no matter how distasteful parts of it

I agree that it is not simple, and that the worst consequences are awful. But unfortunately, opting out is not an option, no matter how distasteful parts of it are. If we don't have competitive or superior tools, we become victimized by those that do. For any definition of "we", where there is not enough social cohesion and control to prevent bad actors (e.g. most obviously: global politics!). These tools are sometimes used carelessly. Some of that is inevitable, some of it is lack of accountability, some of it is malice. Some of it we can improve on, but some we cannot. But also, military research is responsible for huge good parts of our lives. Our survival as a (country, yes, but also) species might depend on it. But it's a mixed bag. This mirrors the complexity of life. The ideal is to have the best tools of competition imaginable, and to never need to use them. We can agree on this at least, I think. (We can also agree that they are sometimes used unnecessarily!) But the privilege of never needing to use them comes with the burden of constantly improving them. Fortunately, there are often great benefits to the research even if it's never used for the purpose intended by the party who paid for it.