I know Grossman's work. Personally I think it's just plain wrong.
He has confused two entirely separate issues, that being a desire to kill with an ability to fight, just as SLA Marshall made the same mistake. Fear of harm is not fear of killing. Most of his evidence fails to make that distinction.
Once you subject a lot of his assertions to rigour they just fall apart. His assertion about man shaped targets and computer games is ridiculous.
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