I'd write that code. I don't believe that violence is wrong. I don't believe that defense work is wrong. I don't have to lean on my ported ignorance of a technology's applications because I don't buy into the moral framework that says that this use or that use is wrong.

Every technology not forbidden by physics is inevitable. If somebody else is going to get a powerful tool to use against me, I'll damn well make sure I have that tool too. And if I can, I'll get it first.

You want safety from killer robots? Make more and better killer robots than the other guy.