And if you disagree with the people ordering the killing, you might not want to fulfill their wishes for new weapons improvements, knowing that they'll use them for killings you disagree with. Or if it makes killings politically easier for them, then it's in your interest to not do that. Why is that unlogical?

Let's say your neighbor starts poisoning all the pets in your neighborhood, would you make poison for them because it's not the poison doing the killing?