“Killing one early on probably eliminates a hundred or more future crimes.”
Very likely much more. Career criminals have been defined as committing 5 or more serious crimes per week. That would translate into thousands of crimes over a career.
http://www.policefoundation.org/docs/catching.html
From USA Today yesterday:
For the first time in 45 years, homicide is no longer among the 15 leading causes of death in the United States, according to an analysis by the Centers for Disease Control and Prevention.
http://www.usatoday.com/news/nation/story/2012-01-10/homicide-CDC-report/52498390/1
Could it be that citzens with guns are making criminals think twice and thus homicide are down?