Zen teacher Jules Shuzen Harris writes in his article Uprooting the Seeds of Anger from the Summer 2012 issue of the Tricycle: The Buddhist Review magazine:

We operate under a common illusion that the things that make us angry lie outside ourselves, that they are external to us. Something out there is in opposition to our need for safety and security; it threatens our comfort or position. We feel a need to defend our vulnerable selves. Anger limits us. But if we have the courage to look at our anger and its causes and learn from it, we can develop an open heart—a heart of genuine compassion.