I suppose anger comes about when we experience a violation of some kind. A boundary is crossed, an action is ignored, or someone attacks you, and we respond in anger. Anger itself comes in many forms: depression, sadness, violence, and aggressive behavior. My intention is not to make a dissertation on anger, but rather to note how angry we are these days.
Then a day like Mothers' Day (yesterday) comes around. All the pictures and words are not angry. There are smiles, genuine words of gratefulness and love. Anger has receded for a day. But doesn't it seem like it's just lying there, under the surface of forced friendliness, ready to pounce on the next person or situation that leads to anger?
One of my favorite lines from the Marvel Avenger movie (the first one) is when the Black Widow tells the Hulk--as the alien invaders are coming hell-bent for destruction--that "Now would be a good time to get angry." To which Bruce Banner replies, right before he transforms into the Hulk--"That's my secret. I'm always angry." And the Hulk uses his anger to help repel the aliens.