I think you're assuming we all know and agree on what evil is. Without making that understanding of evil explicit, we won't really know what we're talking about.

Or, your question could be, leaving evil undefined, could a leader who does evil (whatever that might be) be vindicated by events? That is, could his evil acts be adjudicated (in some way) as good. Perhaps, do the ends justify all and any means?

I think evil is always done to someone (setting animals aside, for this discussion). That is, there is no such thing as evil in the abstract except as an idea (setting aside whether ideas can of themselves be evil), and as an idea it is not evil. To be brief, I think evil can never be good, because the evil done can never be undone, nor can the victim undo it, though he or she may forgive it - or not.

Interesting answer. My emphasis is different from yours, however. What I meant was: is there such thing as necessary “evil”? Does oppression of the powerful to the weak have something good as a result? In other words, would it better humanity to be an oppressive leader?

would it better humanity to be an oppressive leader? — Starthrower

The best leader is a beneficial dictator.

Why do you say so?

Actual I didn't, I think it was Tsu Sun. But I have not read things like that for decades. Just placed it on my reading list, #456.

A dictator allows no one to disobey him and there is no questioning of his orders, as long as those orders were beneficial to the people there should be no problems.

What I meant was: is there such thing as necessary “evil”? Does oppression of the powerful to the weak have something good as a result? In other words, would it better humanity to be an oppressive leader? — Starthrower

I think you're lost in the words ("necessary evil"). Let's put arms and legs on it. I'm the dictator. I take my gun and kill people (who do not by any standard of reason either deserve or need to be shot). Question: can that be (a) good? Or, can you construct any scenario that makes a good of it? And it doesn't have to be just murder, it could be genocide or merely crass robbery - you pick the "evil."