"The Man Who Stole Tomorrow" - Avengers Episode 17
I am, myself, having a problem with Kang's basic premise that Captain America somehow doesn't "belong" in the 21st century. He was active until he was frozen, then sat in the arctic deep freeze as a Capsicle for ... what? Six and a half decades? Then he was defrosted.
He's not an anomaly; he never left the time-stream.
I'm also curious as to why Kang wasn't able to track Captain America's history to the pivotal moment where Cap's presence begins to tip the balance.
My theory goes something like this... Kang's time-monitoring equipment can't actually allow Kang to visit/record/whatever - the observer bit like he did in the micro-episodes - anything close to a time period when he personally manifests, so he was able to track Winghead up along the time-stream and no further. So he sees Captain America defrosted, sees the post-Kree-Skrull War after-Earth, and perhaps assumes that Captain America is the causation pivot.
If he could have presented the Avengers with the specific causation event, it could be avoided without harming Captain America. We know - as an audience - that three things are certain:
1 - Kang does not eliminate Captain America
2 - Kang ultimately fails to conquer the Earth
3 - The Kree-Skrull War fails to destroy the Earth
Any hypothesis must conform to those three fourth-wall facts.
if Kang had been serious about ridding the present of Captain America's presence, then he could merely have gone back a little further to when Cap is still on ice, removed the huge ice-cube, and tossed it into the sun, all without opposition.
I think that Captain America is Kang's scapegoat, as his ego will not let him come to the conclusion that its his own attempt to mess with the timeline of the 21st century that causes his own future to fade; that his time-travel back is part of the timeline, and that his own timeline is a branch always doomed to fade, unless he can learn to not go back - a conclusion to which he's not capable of coming.
Yeah, its a sideways paradox - but it could be the minute one leaves the timeline the first time, one essentially becomes a paradox when one travels upstream, and not subject to normal causation. Kang exists because he didn't exist to interfere - once he does not interfere, he exists to interfere, and once he does, the true 'baseline' timeline - in which another future is written, not the one he traced back to this divergence point - becomes his dominant timeline, and the branch from which he's from is 'pruned'.
The real question for me has become how did Kang's equipment trace Captain America as the causation point, or did it merely bring Kang to the approximate era and Kang himself decided that Captain America was the causation point?
.... or, umm... something like that.