Violence is a controversial term.
In military contexts and among security professional, violence and force are words of the trade. Among the general population, violence is something abnormal and counter to "civilized" life.
In nature, survival really is the correct term for violence, even though violence is the means by which survival is achieved. When violence occurs, there are always two opposing forces being tested. And our terms for these are Offense and Defense. Offense is necessary to survival as much as defense is, and both are manifestations of violence.
We have made so much of our society non-violent that only a small portion of our population has to engage in violence for survival (or a large part of the population for a small portion of time). But when even that small portion is removed, then whole population's survival is in jeopardy.