Obviously you are much less intelligent than average.
Sure, there's a lot of personal satisfaction in capping a bad person in the back of the head but 1) that's illegal and 2) it's immoral.
Sure, there's a lot of personal satisfaction in shooting a bad person in the lower spine, crippling them for life so all they do is shit in bag and roll around their trailer but that too is illegal and immoral.
Same goes with hiring someone to break a bad person's kneecaps with a piece of rebar or a baseball bat. Is going to prison really worth a moment's worth of satisfaction? Not in my opinion.
The best revenge is legal revenge. If it costs money, so be it. Better to spend money than time in jail.
RB, you're a person who thinks with their fists, I think with my brain. That's why it's better for me to let you beat me up, to have you pay for all of my medical bills and for you to go to prison to reflect upon your failures in life. I'll heal in a few days, a few months if you break something. You'll be in prison far longer than that. Not to mention the premeditation on your part probably makes it a felony.
As for defending my country, it's completely legal for me to kill our nation's enemies, both foreign and domestic, without having to give up my freedom in the process.