Ramadan, can you tell me what exactly this hadith is saying?

i think this is some anit shiite propaganda, i dont think that is a very good source. whatever the three first caliphs ever said had been to twist and down play true Islam. Ali (a.s) was not a murderer, EVER. He never killed people who did not deserve to be killed, he only killed in self defense (meaning he was attacked, and the attackers always lost). sorry if i seem riled up but i m getting sick and tired of all this religion war.