Don't build bombs, don't work for the arms industry. Imagine Bosnia without the arms industry - they might still have massacres but with knives and sticks not guns and mortars. If you help design a guidance system then you share responsibility for every death, injury or maiming that that system causes. If you sell such a system to a gangster or a despot or a democrat - you take on responsibility for what is done with that system for as long as it survives. These weapons systems are obscene, they should not have been created they should be destroyed - you should not aid the creation or the dissemination of such systems - get a worth-while job in something more socially acceptable like narcotics or prostitution instead.