Really? There is a debate about this?
1) He attacked Killer B with the intent to kidnap him and pass him over to a criminal organisation, undermining the millitry strength of the country, attacking the brother (adopted or not doesn't really matter) of one of the most importent people of that country. The fact he failed didn't matter, easpically as B took the oppertunity to lie low and explore the land hence they didn't know he was alive for ages until Zetsu said hai, and probably wouldn't have known Kisame had got him at all.
2) He attacked the Kage Summit, interupting diplomatic relations in itself is a seriously grave offence, even between ninja, Danzo was also suspect of this via disruption with his eye.
3) He killed Danzo, a Hokage in all but name with balient hostility towards the Leaf country in general. The fact he was corrupt doesn't factor into the question at all.
4) He mained Raikage and killed several samurai during that summit, drawing several cases of murder and attempted murder.
5) He is a missing nin. That alone means that he's a kill on sight for other countrys at least.
6) He has worked for several, criminal organisations.
And you asked why people don't want him dead? He's a terriorist in the same way that Daradara kills people to test his art, motive doesn't matter as that is a case for another trial, his intent to undermine and threaten not only the millitry strength, but the diplo of the 5 greatest ninja villages is everything. He's on the wrong side intently, pure and simple.