This time it is Moses who has finally learned the difference between appropriate and improper anger, and it is Moses who intercedes with God on behalf of the people. God relents, and provides Moses with the antidote to the snakebites the copper serpent mounted on the head of a staff which served to heal those bitten by the serpents. The Torah seems to teach us so, again and again. Either way, the message is clear. Acting out is not a good thing.
Violence is inappropriate.
Anger management, in constructive ways, is necessary and good. But Pirke Avot does not say that we should not have feelings of anger, or even of violence. Instead, the rabbis seem to acknowledge that which God even teaches by example it is perfectly normal to get angry sometimes. The goal of the heroic existence is to control that anger, to resist the temptation to act inappropriately, to learn not to act out on the violent thoughts and emotions we may have.