Every time someone commits an atrocity we look for explanations. We want someone to blame.
But it is our fault.
We all know someone, who knows someone, who has interacted however briefly with someone who knows someone who is considering committing an atrocity.
Our own behaviour, or failure to comment on theirs, gets passed down the chain with the message “It’s ok to think that”, “It’s ok to be like that”, “It’s ok to do that”.
Remember this the next time you interact with anyone.