I don't believe it is unethical to work on weapons technology any more than I believe it is unethical to be member of the armed forces. We live in a world with bad actors, so some amount of work on defense is necessary for survival.
However, I also believe you are responsible for the consequences of the technology you create. If you decide to work on smart bombs and because of a bad government those end up killing innocent civilians, some of that blood is on your hands. If you're willing to accept the risk of that, I respect your choice.
Personally, I would rather avoid that by not working on that category of technology at all. It's not the kind of mark I want to leave on the world. I do appreciate that I only have the luxury of this choice because I live in a country where others do choose to work on defense so that I can be protected.
However, I also believe you are responsible for the consequences of the technology you create. If you decide to work on smart bombs and because of a bad government those end up killing innocent civilians, some of that blood is on your hands. If you're willing to accept the risk of that, I respect your choice.
Personally, I would rather avoid that by not working on that category of technology at all. It's not the kind of mark I want to leave on the world. I do appreciate that I only have the luxury of this choice because I live in a country where others do choose to work on defense so that I can be protected.