Yeah I learned that the Russians constantly harassed Ukraine for hundreds of years.
If you are leaning towards the former then this could be extended even further: Soviet Union only ever harassed itself. There were no occupied Baltic states, there was no Ukraine, etc etc - just one big happy family called USSR.
No, you just constructed a false dichotomy.
Russian Empire and its successor states USSR and Russia is a product of imperialism that was born in Kiev when Grand Prince Vladimir has brought Orthodox Christianity to those lands. This imperialism conquered some territories, lost some territories (Kiev proper), then regained them back and conquered a lot more, then splintered. The current war is the result of the imperialist successor of the original Kiev regime to gain Kiev back.
If you hold another opinion - that Ukrainians are mixed descendants of people who came to live in this area in ~15 century after it was devastated by Mongol invasions and later steppe nomads plundering in 13..14 centuries, then no, Russia could not have harassed it in 'ancient' times.
Every territory got conquered at some point. Most "Quite Brutally". This is how current countries were born.
Moscow ending up the one who actually pulled it off is kinda ironic, though, given that it was very much an upstart that wasn't even there when Kievan Rus was still a polity united under a single ruler. Goes to show just how effective collaborationism (in this case, with the Mongols) can be to build a power base.
Maybe not bigger, but the people of Novgorod now live in Russia and believe they are Russians. What's with that state-centric view? Ukrainians are Ukrainians despite multiple occupations, but if Novgorodian people believe they are Russians it's illegitimate and they lose all the claims, and are now relegated to have their claims go through Kiev->Moscow. Only "pure" identities with existing independent states can have claims?
This "Ukraine is the true Rus, and Russians are some splinter northern Finno-Ugric goblins" nationalist narrative is just tiresome and incoherent. It's pretty obvious that both sides have about the same level of claim.
Obviously. However their relation to the Novgorodian republic is about as strong as that of modern Italians to the Roman Republic. Also I think any such claims are absurd and absolutely irrelevant (imho this applies to Kiev/Novgorod and to Moscow).
> This "Ukraine is the true Rus.. nationalist narrative is just tiresome and incoherent
Sure, you're right. However this narrative seems to be mostly a response to Russian claims that Ukraine is not a nation and that it should not exist.
> Russians are some splinter northern Finno-Ugric goblins
Nah... Politically and somewhat culturally they are probably closer to the Mongols (I'm actually half serious, the authoritarian and imperialist tendencies ingrained in Russian culture were probably inherited from the Golden Horde rather than Kiev/Novgorod.)