Change happens by listening and then starting a dialogue with the people who are doing something you don't believe is right.
But does that mean that war and violence are inevitable? I would argue not...
You do have to change things as warfare changes.
It always depresses me when people moan about how commercial Christmas is. I love everything about it. The tradition of having this great big feast slap bang in the middle of winter is an essential thing to look forward to at the end of the year.