How many times we have said that to be angry is normal and natural but to exhibit it is unnatural and beastly? But it is worth it! And it is really unrealistic to hope that all human beings should have the same nature - good and noble and without any trace of anger. We are the products of different circumstances we were born into and brought up.
Take what the Buddha said on angry people. The first type of people is like letters curved in rock; they easily give way to anger and refuse to get rid of their anger for a long period of time.
In the second group, it will be like letters written on sand; they too are prone to anger but not for long, just like the words written on sand don't last long.
In the third case, it is like letters written on running water; they too get angry the way we do. But their anger is like the passage of water and does not remain with them to be exhibited and displayed against their 'enemies'.
One can happily say to be angry is in human nature and there can't be anyone without anger. The only difference is that most of us are carried away and fall victims to our own anger. One who uses anger as a weapon of strength is hit more than the one who is targeted.
If you can understand your own nature, then you can use anger as a weapon of strength to improve not only yourself but others as well. And the feeling you get after the positive use of one's anger can be nothing short of bliss.
Anger, when not controlled, blinds us and we lose the power to judge between the good and the bad. The bestial nature of our beings gets an upper hand and takes complete possession over us and make us do monstrous deeds. As Maya Angelou said, bitterness is like cancer; it eats upon the host. But anger is like fire; it burns you!