The Open Source Dilemma

You are the creator and maintainer of a widely used open-source software library. It's free and licensed for anyone to use. You discover that a major military contractor is using your software in a controversial drone targeting system. You are personally and morally opposed to this use of your work. The open-source license you chose allows for this, but you are considering changing the license to forbid military use, which would go against the ethos of 'free and open' software and could alienate many of your users.