Er... this is only some boring rambling, but I think a gun is a *very* poor example, as using it probably leads to a (probably unwanted by the victim) death, which is always a bad thing, as deaths are not undoable. IMHO human life is more valuable than some things this thief might have stolen.

Chemistry is a better example, as it has helped mankind, but also developed poisons etc.

Most humbly yours,
opqdonut