why was he there in the first place?

He doesn't need a reason. And he had infinitely more ties to the area than any of his attackers, given that his father lived there, he had worked there, etc. It's literally his community.

Inserting yourself into a dangerous situation so that you have an excuse to shoot someone in “self defense” is vigilantism.

Textbook victim blaming. By this logic, a woman knowingly walking through a bad neighborhood is to blame for any rape attempts made on her. After all, she 'inserted herself into a dangerous situation'. So if she fights back against an attempted rapist and they get injured or killed, she's a 'vigilante', according to your reasoning.

Absurd. It's so obvious how deeply bias has twisted your thinking, because I'll bet anything you wouldn't victim blame that hypothetical woman in the exact same analogous situation the way you did him. But that is the argument you made.

why was he invited to speak at political events after the fact? Lots of people have their “life threatened for no reason” and exercise their right to self defense, none of them have been invited to speak at political events.

Because liars on the left unwittingly turned him into a champion of the ideologues on the other wing, by saying a bunch of bullshit about him that was directly proven to be false; that he was a racist white supremacist mad gunman who shot (black, at first, lol--it was a long time before it stopped being common for leftist ideologues to stop claiming it was black people he shot) people for no reason.

It was a massive mask-slip for the ideologues of the American left, clear evidence that they're just as eager to latch onto even obvious bullshit, when it confirms their biases, as any whacko on the right. Even now, years later, there are still people getting basic, firmly-established facts about that day completely wrong.

Even your characterization of him going to Kenosha because he wanted an excuse to shoot someone is a lie, nothing less. He did everything that someone 'looking for an excuse to shoot someone' WOULDN'T do:

• Never aggressed on anyone, either verbally, or physically (no 'fighting words', no brandishing of his weapon, no pointing the gun at anyone, nothing)
• Never escalated any aggression directed at him
• Consistently fled at the first sign of physical aggression directed at him
• Only ever used his weapon in situations where he would have been literally murdered otherwise
  • A guy who verbally threatened your life in no uncertain terms (literally "I'm going to kill you!") has chased you down and cornered you and is now trying to wrestle your gun out of your hands
  • A guy who successfully took a full swing at your head with the metal trucks of a ~10 pound skateboard, an attack that Rittenhouse is lucky didn't kill him, and was now in the act of trying to take another swing with it
  • A guy who literally put his (illegally-possessed, unlike Rittenhouse's weapon, by the way) handgun in your face after pretending to lower it.

We know everything he was up to while he was there. He didn't provoke or try to intimidate anyone. Before he went to the protest, he spent the morning cleaning graffiti off a local high school. When he showed up, he literally spent hours walking around, giving first aid to anyone who responded to his shouts of "medic!" and "friendly!", handing out water bottles to protesters on request (he did NOT counter-protest at all), and putting out fires, in between spending some time standing guard at the car dealership he was asked to help defend.

His first aggressor was a suicidal (literally--Rosenbaum had been released from a hospital after a suicide attempt THAT DAY) maniac who lost it after a fire he set was put out by Rittenhouse's group, LITERALLY screaming "I'm going to kill you!" before chasing Rittenhouse down while he tried to run away and then trying to wrestle his gun away from him.

Bottom line: I've paid little to no attention to Rittenhouse beyond the Kenosha case, but I am very familiar with the facts of that case, and Rittenhouse literally did nothing wrong in Kenosha that day. Nothing. It's obvious he went to Kenosha with nothing but good intentions, considering everything we know about what he actually did while there, and every significant action he took there that day (with the exception of the self-defense acts, which I consider amoral/morally neutral--it's human nature to protect your own life) was, objectively, benevolent.