That's not how civilized people should approach violence or warfare, even when violence may be justified.
Look at the aftermath of WWII, for example, many of the most bitter enemies (such as the US and Japan) forged bonds of friendship and alliance and today live in peace with each other, contributing more towards each others' prosperity and happiness than anything else. That's how conflicts are truly ended, the chaos of the battlefield is merely a tool that allows you to get to a point where such things are possible, and if that opportunity is wasted then you have done little other than to perpetuate or create yet another vendetta.