Many artists have their own way of delivering a song. If the song is a protest song, or a song of anger, they will be able to put across the message in the way they best communicate with the audience.

Two examples:

Leadbelly is very angry when he sings the Bugois Blues. He was known to be a quick tempered and violent man, and the song is based on his experience of discrimination; but he still doesn't spit out the works with his teeth clenched. Even the guitar playing is not as hard-driving as it is in other, less angry, songs. The message hits me whenever I hear it. Even in 1997.

Billie Holiday is very angry when she sings Strange Fruit, but she sings it like Billie Holiday and she talks to me.

On the other hand, of course, Johny Cash's Sam Hall would be flat if Cash doesn't sing it angrily. Of course, this is a style in which he works very well.

Murray