There are, of course, people who insist that anger is never, ever appropriate. They are wrong. Anger is a natural human emotion, and as such has its place in our lives. Anger also has its uses.
Anger can drive us to defend ourselves instead of flee. It can drive us to defend others instead of stand by and watch, seeming to lend our approval to attacks on them. It can drive us to succeed against great odds. It can drive us to do things, good things, great things which we otherwise might not achieve.
Anger can also serve as a warning. When we get angry, it lets people know immediately that whatever they have done is not acceptable to us, that there is a real problem here, that they have hurt us. It draws a line: You may not treat me that way. And it does it in a way that no calm way of saying it can do.

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