There are many causes for anger in this world. But the mercy of God is not one of them. In our anger it may displease us to recognize that God's mercy extends to our enemies. The good news is that, angry as we are, it extends to us as well. And he fulfilled that dream.
Anger equals survival.
Meekness isn't an option when there's a guy down the alley who probably has a gun. And you better believe that I get angry at the things that I see. Back when I first went on the job, all charged up about becoming a cop, I never dreamed that all these years later I would spend as much time as I do just praying for peace of mind, just praying that my own anger doesn't make me do something crazy.