Well, it wasn't necessarily a final CS in case you wanted me to modify anything.

 As for Johnathan's disposition against chemicals and gasses isn't so much a phobia but a strong fear of that particular kind of death. He'll keep his cool through most of it and just be very disturbed, unless it gets really bad.

 As for his self proclaimed "killer" status, that's mostly just hot air. A surprising number of people join the infantry and other combat roles wanting to cause death, pain, and destruction, at least in my experience. Shapiro's feral desires were strong enough to deny a posh life in Ohio and risk his citizenship in the US just because of his eagerness to fight.