I studied karate for many years as a teenager and never put it to use until I was about 25 years old and some drunk in Newport RI ran my girlfriend off the road on her bike. I chased the guy down who jumped out of his car and came at me. With me still straddling the top tube of my bike I blocked every one of about 10 punches the guy threw at me but couldn't bring myself to strike him back. Eventually I grabbed his wrists and held them till he calmed the f... down. Fortunately, a cop came by and took the guy in for being drunk and disorderly.

That is the full extent of my violent past and I have no desire for more violent interactions.