Congratulations! Now What?

I'm going back to Trigun tonight, specifically the last episode. So if you don't want that ruined, better mosey on.

When the series was all said and done, we see Vash hauling his batshit crazy brother Knives back to the town Meryl and Milly are working in, just as the town hits water. Hooray! Humans may be able to sustain themselves! My question is, what does Vash intend to do with Knives?

Knives is shot, so the first thing will probably be to get him patched up. But then what? Knives still hates humans; that isn't going to change just because Vash beat him and left their city-destroying firepower laying out in the desert. And Knives was able to draw underlings (the Gung-Ho Guns) to himself even when he was only half a person, so is it really going to be hard to continue with his "Exterminate Humans" plan?

To a certain extent, this is what Spider-Man deals with when it comes to Norman Osborn, except it's even more dangerous. See, Norman is obsessed with Peter (not Gwen, JMS!), and so his actions will always lead back to trying to hurt Webs.

But Knives hates humans. All humans. Period. They're inferior parasites, and he wants them gone. He also wants Vash alongside him, but really, Vash is just an impediment to his plan. Knives would be perfectly fine with escaping quietly, and going about his business far away from Vash, dealing with him only when it becomes necessary.

So is Vash going to throw him in prison? For what? Knives can't be directly linked to any crimes; either the Gung-Ho Guns did it, or there's no one left to testify besides Vash. And I don't think "The Humanoid Typhoon" is going to be the most credible witness to most people.

So that leaves Vash with the option of forever keeping an eye on his brother, making sure he doesn't start up again. I get that Vash isn't a killer, but I don't honestly feel he thought this one through very well.