Exaggerating a bit, I felt like my old self was dead and I just happened to somehow have inherited his memories. But a more concrete thing: While before I might have been saddened about bad things happening to kids, like any normal person would, after having kids myself I experience an stronger reaction: I get almost physically ill when I hear about kids getting harmed.
I had a spell of absurd anxiety. I’m not the same person in many ways. Being a dad is frekking cool and the weirdest challenge of my life.
And to your last point… I’m such a chill, no-violence dude, but once a drunk teenager walked into us and yelled at my baby. I was shocked, but 5 seconds later I only wanted to have access to a gun to shoot that teen right there and then. Yikes.
I don’t think any children should be harmed in a conflict. The knowledge of that, or of what we used to do to children in the past, are both things that can ruin a day for me.