The problem with making Self Defense a straight easy out is you can just claim anything is self defense. I have not watched in in ages but I think it was a South Park episode where they outlawed hunting or something except in defense. So the hunter guys would go out and Hollar, "It's coming right for us!" Before shooting the animals.
In England the common law on self-defence is well-summarized here:
It works, by and large, because we don't allow civilians to travel 20 miles to parade around in trouble spots, taking with them firearms in case they need to defend themselves. As the Governor of Illinois puts it
There's also the unpleasant fact that a great deal of the history of the Second Amendment was to ensure that local white militias were able to put down rebellions and revolts by the enslaved, and to make sure the enslaved had no access to firearms (to the extent that South Carolina, during the American War of Independence, threatened to surrender to the British rather than accept any Black volunteers, enslaved or free, to fight the British.
Similarly, post-Emancipation, it's been used to ensure that White militias are able to protect other White citizens from what they perceived as lawless mobs of darker-skinned peope, just as Mr Rittenhouse doubtless thought he was doing.
While, in this as in so many other ways, a document drawn up during the C18th to accommodate the concerns of a landowning aristocracy based on racialised kidnapping and forced labour doesn't really work too well for contemporary conditions, maybe one way forward, without tinkering with the Second Amendment, might be to introduce a distinction similar to the one we have in the UK between Grievous (i.e. "really serious") Bodily Harm, contrary to either Section 18 or Section 20 of the Offences Against the Person Act 1861, with Section 20 covering Grievous Bodily Harm With Intent, which is a considerably more serious offence than Section 18, simple GBH.
If there's a fight and I strike out at my assailant, either with a hammer I happen to be holding at the time or have instinctively grabbed to defend myself, then if I cause sufficiently grave injuries, that's GBH. If I take a hammer with me, though, because I think I may need to use it to defend myself, then that's GBH with Intent, and I'm looking at a much longer sentence. If I pick something up in the heat of the moment, it's a jury question, but if I took it with me without a very good excuse (I'm a carpenter on my home from work, for example) then it's almost certainly Section 20.
I wonder if something similar could not be used to distinguish between lawful and unlawful self-defence. Presumably the only reason Mr Rittenhouse armed himself before travelling to Kenosha is that he thought he might need to use a firearm for self-protection, which makes me want to ask him why he didn't simply protect himself by staying at home that night, since he wasn't acting as a sworn member of law enforcement, national guard, sherrif's posse or anything similar.
While I'm not sure I'd want to remove the right to self-defence completely, I do think that in cases where the defendant's only reason for carrying the weapon which he killed the victim was to protect himself, and it's not something he would nomally have about him, then it should be sufficient to mitigate the charge to manslaughter.
