I don't buy the "none of our business" argument. That's the type of "us" and "them" distinction that has dominated human history and led to these cycles of behaviour in the first place. We need to decide that we're humanity, we're not Country A and Country B, and make the first steps of acting like it.
If your next door neighbour is getting murdered, is that none of your business? I'm guessing most of us would call the police not just out of fear for our own safety, but also because we genuinely don't want that person to get murdered.
It's easy for us to sit in our relative peace and comfort and make absolute decrees like "We will not get involved on principle." Afterwards, we get to have dinner then flop on the couch and watch TV. That's the benefit of being lucky to have been born in our respective countries. Meanwhile, there are millions of defenseless people living in the paths of these types of psychos who pay an immense price.
We shouldn't do it because we expect to be given parades and have flowers thrown at our feet, we should do it because it's the morally correct thing to do and because as humanity we should decide that this shit is unacceptable anywhere.