Armed separatism in Donbas exists only because Russia makes a deliberate effort to support it.
There was no violent separatism in Donbas until march of 2014 - for over 22 years that Republic of Ukraine was an independent state. There was no need because citizens of Ukraine and Russia enjoyed very similar legal privileges in each other's countries. When the protests began in 2014 they were peaceful in nature and were directed at the ousting of Yanukovych and the formation of a government by pro-western and nationalist politicians as well as efforts by nationalists to ban Russian language etc. in a deliberate attempt to further destabilize the country because they saw that as their only way to more power.
Ukraine despite Russian claims is not a nationalist country and largely rejects Bandera's ideology. Banderites were only relevant in lands that were under Austrian rule from 1772 to 1918 - Galicia, Volyhnia etc. In 2015 there was a local election and nationalist parties as well as the electoral list of Arsen Yatsenkuk got only a
handful of seats in local councils. People elected Zelensky because he promised the return to "normal Ukraine". Both the nationalists and pro-Russians were fringe minorities rejected by the society. The reason why they are so visible is because they dedicate themselves to their political causes - similarly to how MAGA and LGBT/BLM are over-represented in the US.
Similarly pro-Russian Ukrainians or ethnic Russians in Ukraine were often against Russian takeover. They had no problem with Ukraine as a state because the history of Ukraine as a politically sovereign entity is long. Ukraine was one of the three founding member states when the USSR was created. It is one of the founding member states of the UN! USSR in the beginning was much more like EU today - a confederation of independent states - than the centralized USSR at its end. Gorbachev's
pyerestroyka was attempting to revert those centralizing changes and bring USSR back to its revolutionary roots. This is where "Commonwealth of Independent States" came from.
The notion of what it means to be "Ukrainian" is the problem because "Ukrainians" were invented by Austrians (Germans) as means of controlling the local population. They couldn't refer to the historical name of "Rus" or "Ruthenia" because Russia (pronounced:
rassiya) is a Muscovite word for "Rus". In effect you have the conflict between "Kievan Rus" and "Muscovy Rus" which is somewhat like the conflict between RoC and PRC where Chinese people on Taiwan got the idea that they are not Taiwanese Chinese but Taiwanese. And that has to do with religion. Ukrainian nationalists of OUN (Organisation of Ukrainian Nationalists) were Catholic because they were Austrian supporters while the majority of Ukrainians are Orthodox. This is where a lot of the initial confusion came from because today most people in the west don't recognize how much of a role religion played in shaping of political identity a century ago. "Ukrainian" was Catholic while "Ruthenian" was Orthodox and because of the role of Russian Tsar as in Russian Orthodox church in the course of war it shifted toward anti-Russian for Catholics and pro-Russian for the Orthodox.
This is the confusion that underpins the conflict around identity. Today there is a state called "Ukraine" and two movements make a claim to "Ukrainian" identity. One based in that old anti-Russian identity informed by religion and conflict and one based in current Ukrainian citizenship and the legacy of Ukrainian Radiyanska Socialist Republic where "Radianska" is Ukrainian for "Soviet" from "rada" meaning "council" in Ukrainian.
So my point is that the people in Donbas went out in the streets to protests which lasted throughout March of 2014. And then FSB smuggled in armed thugs (among them Igor Girkin) who took over city councils by force and established "Donetsk People's Republic" on 7 April 2014 and "Luhansk People's Republic" on 27 April 2014. The Ukrainian government reacted by starting an anti-terrorist operation and rightly so because the DPR and LPR were terrorist entities engaging in de facto and de jure acts of terror. In the beginning people didn't think much of it because many ethnic Russians pushed for federal structure in Ukraine and thought that DPR and LPR could be a beginning of that process. (That's why Yanukovych's party is called "Party of Regions" by the way). The problem was that the army was disorganized as a result of the coup and anti-Yanukovych purges but by June they put things somewhat in order and began a coordinated operation. It also helped that Poroshenko was elected president in an election that was considered legitimate compared to what happened in February. By August Ukraine almost regained control which is when Russia intervenes directly in Ukraine and that established the territory of DPR and LPR that existed until 24 of February.
As far as Russians who were Ukrainian citizens went there would be no armed insurrection as least not until governmet in Kiyv would begin to repress them. It's not that they considered themselves Ukrainian. It's that it made no sense much as it makes no sense for Scots or Welsh or Irish to complain about living in England.
Separatism was entirely orchestrated from Moscow as means of destabilizing the country and preventing Ukraine from legalizing status-quo without Crimea to join NATO with a completely invented narrative of "genocide" to accompany it. Ukrainian nationalists would be a problem but they were removed from power in the next election along with most anti-Russian hawks. Poroshenko lost the election because he turned toward them in the end as his popularity dropped.
I understand that it's difficult to get a clear picture on Ukraine in a place like SDF but that's what happened. There was no conflict between Ukrainians and Russians. It was always a conflict between Moscow/Putin and Washington over imperial spheres of influece and energy markets with pro-Russian and pro-Western oligarchs taking sides with hopes for power. People could argue and disagree but they would not fight. They've lived side by side for decades as part of one political entity.
You mean like the terrorism and dissent that England has in Wales? Or in Scotland? The terrorism in Northern Ireland was sectarian violence between religious groups of Irish. Republic and the UK had perfectly amicable relations by then with a Common Travel Area and essentially the same rights for citizes of both countries.
Look what happened in Basque country and how the Basque - a genuine separate ethnicity and culture that has nothing in common with the rest of Spain - treated ETA. Hint: not well.
There's no reason why "Taiwanese" people have to conduct armed struggle against China unless there is external support for it like in Xinjiang.
Even if they abandoned the notion of restoring RoC KMT were still in favour of reunification that allowed them to remain nominally in control of the island - a confederation like the Union State of Belarus and Russia. KMT do not support independence because their very political identify and interests are against it. So no, Taiwan is not a "100% separatist entity". There's a reason why US and Japan put so much effort into maintaining DPP in power.
DPP is the 100% separatist entity and even then it's mostly for show because they know how unrealistic it is considering Taiwan's growing economic depedancy on China.
Japan does it only because US enables it as more convenient way of stimulating separatism that seems "genuine" for ignorant Americans and Europeans. With US out of the picture there is no 'Taiwan separatism" any more than hippies were ever a serious threat to American establishment.
