I had the pleasure of holding a talk at the same event as Saeid Esmaeilzadeh, a rockstar entrepreneur and chemist in Sweden, and one of the questions he got during his talk was how he could reconcile his drive to be an ethical businessman and supply stuff to the military. His response was pretty long but it made a comparison with the sugar industry (paraphrasing here, sorry Saeid if you're reading this and I got something wrong):

"I would never force my ethics on someone else, I will however criticize someone if they don't think their business model through on an ethical level. You should be able to live with what you're doing, personally, without deluding yourself or being in denial. I think Sweden, a democratic country, has an obligation to make sure that the troops we send for peace keeping purposes have the right gear to do the job. However, I would never, ever, supply stuff to the sugar industry. Even though we've found loads of stuff that could be applied to that field, I just couldn't live with myself. It serves absolutely no utility to humanity, it kills more people every year than war and you're primarily marketing stuff to children to form life long habits. It just doesn't square with my morals but I've met other, smart people who have thought long and hard about the sugar industry and came to the conclusion that it's an ethical industry. Whatever floats their boat, but I don't want to make money that way."