I agree with Katz that men are not entirely biologically more aggressive.  I agree that most of men being aggressive is obtained in the environment men are raised in. Men are taught to not show fear or pain and not be a chicken because that's just what men are supposed to be like.  If a man is anything else it is considered weird or wimpy just like the author said.  its no coincidence that men are the shooters in these shootings because men are taught to be more aggressive.  if men were not raised in these environments men would not be like this because we are not biologically wired to be this aggressive.