Strength/energy and the people around us

If I was walking along, having a good day, and someone knocked into me in the street I might get annoyed, but would probably soon forget and forgive (they probably didn't mean it). In the same situation if I were stressed, I'd probably get angry and maybe even shout at them. If I shout at them, then they become stressed and are more likely to shout at someone that bumps into them.

This is a simple example, but the concept can be applied to society as a whole: negativity is self-perpetuating.

One solution to this would be to entirely eliminate negativity from society (I know this would be difficult/impossible, but bear with me on the theory). However, some negativity is good for us: we learn from our mistakes.

So, how should society balance a healthy level of negativity with the risk of self-perpetuating negativity consuming the world?