Right, we all have a responsibility to act ethically in all parts of our lives. Refuse to work for organizations that do unethical things; if you are in an organization, refuse to do unethical things even if it gets you fired. Do not facilitate the doing of unethical things in any way.
The difference with the military is you can be put in prison for behaving this way.
Not at all. If enough people refuse to compromise their principles, the labor supply will shrink for that org, and therefore their hiring costs will increase, leaving them fewer resources to achieve their unethical deeds. "I'll change it from the inside" is a lie people tell themselves, but in reality they get steamrollered by the internal processes. If you don't have a backbone at hiring time, why would you grow one down the line when you're already dependent on them for your livelihood? No - do your part and refuse to play.
The difference with the military is you can be put in prison for behaving this way.