What do you think of these theories?

3 theses on the Russian-Ukrainian war:

1. Putin's decision to start the war on Ukraine isn't foreign policy. It's domestic one. Putin first consolidated his power through the war in 1999-2000 and it worked. So he repeated this trick every time his popularity started waning🧵

Putin was confirmed as the Prime Minister on 16 August 1999. By that point Yeltsin chose him as a successor and Putin controlled intelligence. But he still had to stand on elections - and he was unknown. His rate of approval was between 3-4% because ppl didn't recognise his face

Just two weeks later apartment bombings started. Since September 4, a number of residential houses in Moscow, Volgodonsk, Buinaksk were blown up. More than 300 people died, 1700 were wounded. Putin accused Chechen terrorists in these attacks and invaded the separatist region

He won. In the course of the war he built his 
as a tough victorious military leader. And Russian public opinion likes victorious military leaders. By the end of the year with the Chechen resistance largely crushed, he became very electable. That's how he became a President

Of course, the entire story with so timely blown up houses looked kinda shady. There were certain suspicions regarding who really organised these attacks, especially in the context of the Ryazan case

With all these explosions, the country became vigilant. On September 22 Alexey Kartofelnikov living on Novoselov 14/16 in Ryazan noticed a strange white car parked near their residential building. Its passengers took several bags and brought them into the basement of the house

After the strangers left, locals called the police. Police came and found several large bags from sugar - with a detonator. People were evacuated and the police expertise showed that the bags contain hexagon. Next day it became the national news - the media were still free

Prime Minister Putin congratulated them with preventing a terrorist attack. The same night police (police is MVD - different from FSB) arrested two suspects. To their surprise they showed the FSB IDs. Ofc Moscow HQ of FSB called the police and ordered to release their agents

Next day Putin gave a different version. Now he said that those were simply the trainings, the manoeuvres. The FSB was learning how to prevent terror attacks and these bags contained regular sugar. The detonators were fake

It all sounded shady. But the military planes were already raising Grozny to the ground. Successful invasion that followed changed the electoral balance completely. In August 1999 2% voters would vote for Putin, in 2000 - 53% did. Russian people love victorious wars

So, it worked. And that's how the institutional inertia dynamics commence. Whatever worked out in the past, will likely work out again. So why bother with making up new ideas if older ones are completely reliable? And indeed, reliable they were

In 2010s Putin was clearly losing popularity. Fraud on the parliamentary elections of 2011 triggered the largest street protests since Putin came to power. That was a bad marker. Economy was rising, quality of life improving. And many were still angry

But streets protests could be ascribed to a politicised minority, whereas silent majority supported him. That's why he confidently came to a boxing championate to give a speech, with the federal TV broadcasting it in real time. And he was booed with millions people watching

That was a heavy blow. He came to power as a victorious military leader. But now, 11 years later, ppl didn't recognise him as such. They saw him as a pathetic gerontocrat with too much botox fillings. He became a joke. So he had to take urgent action to be treated seriously again

His popularity falling, he had to restore his 
as a serious leader. How? Well, by winning wars. Again, he initially built his legitimacy through a military victory, so why not do it again? Thus Russia engages into wars: Syria, Ukraine, Africa. Domestic policy by other means

So the real audience of this play are neither Ukrainians, nor Westerners. It's Russians. Of course many won't wholeheartedly support the war. But it will make them take Putin seriously. And for Putin it's much better to be regarded as bloody and merciless, rather than ridiculous

2. Many in the West exaggerate how robust the Putin's regime is. It's not only dependent on Western technologies and imports, it also can't decrease its dependence without a renegotiation of power balance. Which means it exists only as long as the West doesn't take action

Infrastructure-wise there is one thing it's doing well - building and maintaining communications for exporting raw materials. Railways, pipelines, seaports

And yet, sanctions obstruct development of new oil or gas deposits. There are new deposits introduced, but they don't compensate the depletion. Theoretically Russia has huge deposits, but they're primarily on Arctic shelf and Russia lacks the technology to extract them alone

Russia is not the USSR. The USSR was a theocracy legitimised through technological progress, which valued scientists and engineers highly. Modern Russia doesn't. Consider salaries which state corporation offers to aerospace engineers - kinda 150 usd/month

That's important to keep in mind. Unlike USSR, Russia doesn't value people who produce stuff. It's not prestigious, it doesn't pay. So whoever can leave to the IT and work for international market directly, will do it. There's huge negative selection in production of hardware 
Which means that Russian industry, including military, is highly dependent upon Western technologies and equipment. Precision manufacturing is done on German, Swiss, Italian machines. Production of literally anything complicated continues only as long as it is allowed to continue

3. What will be the result of this war? That largely depends on Western, primarily American reaction. If Putin manages to win a small victorious war again and get away with that, it will not only increase his authority but trigger tons of terrirotiral conflicts all over the world

Let's be honest, in most countries there're groups who believe that their neighbours occupy a piece of our sacred land illegitimately. That's very typical feeling and usually it's mutual. The only reason why wars over the land don't happen more frequently is the fear of reprisals

If this invasion succeeds and Putin gets away with it, this will trigger a chain of imitators waging their small victorious wars all over the world. More powerful powers than Russia will certainly do, less powerful ones will try their chance, too. That will be a very bloody era

Paradoxically enough, even the military defeat of Russia is not necessary to prevent that scenario. Simply Putin losing his power would be enough as a warning. And counterintuitively, that would likely result naturally if he doesn't achieve a quick victory

There's a big difference between an easy war and a hard war. An easy war makes regime stronger because it achieves victory without having to transform. But a hard war will transform it. The longer WWI lasted, the more the real power over Germany flowed from Kaiser to Ludendorff

Russia plays hard. But hard war is incompatible with the state security rule. They aren't guys who do stuff, they are the guys who find wrongdoings in the work of others. Critics, not doers. So once the war becomes existential, power will start flipping from their hands. End of🧵

https://twitter.com/kamilkazani/status/1496711906412933121

https://threadreaderapp.com/thread/1496711906412933121.html

I think the idea of NATO as an ideologically neutral, purely defensive alliance is a very western perspective. I think Putins perspective of NATO is more akin to our picture of the Warsaw Pact: Neutral defense on paper, but blatant ideological warfare and power projection in practice and intent. If you view NATO in that light (whether accurate or not), NATO's expansion eastward following the fall of the USSR looks like a blatant power grab while Russia was weakened. If you also have a view of all the former parts of USSR as essentially part of the "real" Greater Russia, the expansion of NATO into not only former Warsaw Pact members, but USSR states as well looks exceptionally aggressive. 

A faulty comparison, but perhaps useful as an intuition pump: 
Imagine if the USSR hade in fact "won" the Cold War in a similar fashion to how the West did; by essentially economically outproducing the USA, until it collapsed financially (only one limited version of events I know, but bear with me), resulting in many US states being left to their own devices after the shattering of the Union, all media being invaded by communist propaganda, and lots of Eastern thinkers and commentators having an opinion on the NewUS's constitution and internal affairs. You asked them then to guarantee your safety, and in response got vague promises of being left alone. In the years that followed, before the NewUS had time to re-consolidate, the Warsaw Pact expanded (by propaganda and bribery) to include most of Europe, Central America, and Mexico. It didn't change in character, instead it grew rich, but lazy and complacent with it's own success, ever self-righteous and condescending. The newly (temporarily?) independent states of Alaska, Arizona and New Mexico followed a few years later, over your protests. By the time the NewUS is starting to emerge from the ashes and have some power to wield again, however hobbled and outmatched, the independent state of FloriTexas, representing a huge portion of former US population and influence, and by many considered part of the former USA's "heartland", starts the process of joining the Warsaw Pact. This process involves the careful dismantling of everything a patriot would call "American" about the place. You were a lowly CIA spy when the old US fell, but you're now the President of the remaining 32 states, and have been pleading, arguing and maneuvering for the communist states to Just Leave The Fuck Alone, Like you Promised but to no avail. The people around you in government are weak and have lost vision. You yourself are growing old. If you ever want to realize the dream of a reunited USA, FloriTexas is the Line in the Sand, the Last Chance for that to ever be possible. A Fall from Grace, and a Destiny Unfulfilled. What do you do?

Of course there are many problems with this comparison. I won't try to list them all here, think of it only as an intuition pump. But in this view, the Warsaw Pact/NATO looks very threatening.

Even taken at face value, this represents at best a caricature of the Nostalgic/Patriotic USSR perspective, and of course Putin is a shrewd intelligent man who probably won't adhere to any such simplistic narrative. But to the extent that I understand what is going on at all, I think this tugs at similar heartstrings. Tugging heartstrings is of course not the same as legitimization. Among many other problems, this view of NATO and "westernization" doesn't care about democracy or national self-determination at all. But of course, that seems to be quite true for Putin. 

Now, that being said, I don't agree with the view of NATO as purely a neutral defense pact. It in fact places clearly ideological conditions on it's members, some of which are overtly political: (emphasis mine) "Countries aspiring for NATO membership are also expected to meet certain political, economic and military goals in order to ensure that they will become contributors to Alliance security as well as beneficiaries of it.". There is also the fact that the USSR tried to join NATO when it was first formed (or rather, they called the bluff on it's neutrality), and both Gorbachev and Putin have allegedly floated the idea since (wikipedia source only, sorry no time), but it was dismissed as "a dream".

So much for the historical backdrop. As for the war itself, it does of course look like a huge mistake right now, from the western media perspective. I am leaning towards that perspective holding up, but that is not quite settled yet I think. It is largely based on the premise that Putin thought he would win in a few days, which is often recited, but I have only seen a few smallish pieces of evidence for this myself (could easily be that I missed it, please enlighten me. Mainly the accidental(?) publishing and subsequent retraction of pre-written news articles lauding Russian success). If Putins plan all along was to slowly but surely take Ukraine using slowly advancing tank columns supported by heavy artillery, like the Russian army does best, then it would have been in the US interest to oversell Putins plan to start with, so that he looks weak now that negotiations are starting. There might be some of this going on, but in the end I think I basically buy the "huge mistake" theory. Taking Crimea was a huge success for Putin domestically, and was very easy for him to pull off at the time. It could have worked a second time.

This is only my take, apply salt as needed. I am but a lone keyboard warrior in a big big sea of history, propaganda and geopolitics.

All of the previous wars have been easy to understand. From the pure will for power and territory of most of the old wars, to the stupid escalation of WWI, to the megalomania and extreme nationalism of Nazi Germany leading to WWII, to the need to cut short Communism's expansion with Vietnam and Korea, to the religious fundamentalism of the wars in the Middle East, to the ethnic tensions of Yugoslavia/Kosovo and pretty much all modern wars in Africa.

This has already been pointed out but I need to say it again: wars are not easy to understand. If you have tidy and simple explanations of wars from the past, that's a sign that your understanding is poor and distorted, not that events in the past were actually as simple as you think they were.

But I can't understand this war. The official motive, as most of us would agree, is b.s. NATO's expansion poses no threat to a country with the greatest nuclear arsenal on Earth.

What was the motive behind the Soviet Union attacking Finland in 1939? Molotov (the Soviet minister of foreign affairs at the time) in fact gave the same excuse that Finland was a threat to the Soviet Union in a meeting with Hitler, and Hitler said that it was ridiculous for the USSR to claim Finland posed a military threat to them. In response, Molotov said that Finland was a "moral threat", and it was unacceptable for a great power like the USSR to have a defiant small country like Finland as a neighbor.

There are some parallels to today's war over Ukraine, since a militarized Finland posed a real threat to Leningrad in the event of a war, and in the eventual war between USSR and Germany, Finland indeed sided with Germany and together their forces were able to besiege Leningrad for three years. Moreover, Finland had been part of the Russian Empire until 1918 and Stalin did have ambitions of restoring the lost territory of the Russian Empire, much like Putin might harbor similar ambitions today.

I think the official motive is not "bs" at all. Russia's actions are perfectly explained by concern over NATO expansion and not that well explained by any theory that doesn't include concern over NATO expansion as at least a factor that went into the decision to go to war. You might think that their concern is either misguided or irrational, but that doesn't make the concern any less real from their point of view.

Is it really about nationalism and the desire the re-unite the old empire? But those "heroic" pursuits don't seem to hold water to me in a world more and more globalized and money-driven. Ideology is dying (and that's good).

Maybe you're wrong about your grand model of history. What gave you the impression that "ideology is dying"?

In 30 years, we’ll have the same tidily packaged explanations for this war that we have for wars of the past. I expect that wars of the past were also confusing at the time.

But if you’re this shocked, it’s a sign that your old model of how the world works was probably flawed. Rationality 101! In this case, maybe foolish and ideologically-driven decision making is more common than you’d assumed.

Because Ukraine is turning westwards. NATO is a small part of this, and largely irrelevant; it's not as if Putin's attitude to Ukraine has changed as it has become more likely to join NATO, or as if in the short or medium term it has ever been at all likely that Ukraine will actually do so. 

Ukraine sees the healthy democracies and economic growth of other Eastern European countries, and wants to be one of them. This desire has been increased by the failure of the Russian economy over the past ten or so years; since 2013, Russian GDP has decreased by a third (or flatlined at PPP). The GDPs of Eastern European EU member states have continued to increase. Ukraine's has continued to stagnate.

Even if denied membership of NATO, the EU, and every other supranational political organisation, in perpetuity, Ukrainians will still want to escape Russia's orbit, and as long as Ukraine is a democracy (even if a seriously flawed one), they will try to do so. And as the gap between the Ukrainian economy and those of other Eastern European countries increases, they will try harder.

Putin doesn't have a way to change this short of having Ukraine run by a dictator dependent on him for survival. Putin can't increase Russian economic power, because he runs a mafia regime where his associates control and mismanage everything, and the only way to improve the economy would be to get rid of him. Not to mention the impact of the pre-existing sanctions, which again can only be removed by getting rid of him. He can't increase the attractiveness of the Russian state and political model, because he's a mass murderer who runs a mafia regime, and the Russian state and political model can only be made more attractive by getting rid of him.

And all European countries are trying to stop using fossil fuels by 2050. And seem to be serious about doing so. Which means that in any realistic forecast, a Putin-controlled Russian economy is going to do increasingly badly over the next three decades. 

The war would not have happened if Putin had not given the order for it to happen, and if someone else was in Putin's position then it seems unlikely that it would be happening. No one knows what's going on Putin's mind, and so no one can be sure why the war is happening. Maybe he's become obsessed with Russian greatness and expansion, maybe he fears Russian decline will lead to his overthrow, maybe he's hooked on meth and in a state of paranoid psychosis, maybe he's obsessed with Ukraine in particular becoming part of Russia, maybe he fears the collapse of the Russian Federation if its non-Russian inhabitants see a dependent country leave the Russian orbit and succeed, maybe he fears the collapse of his regime if Russians see a democratic Ukraine succeed, maybe he thinks that he's the reincarnation of Peter the Great, maybe he believes that Russians in Ukraine need his protection, maybe he thinks that Russians everywhere in the old Eastern bloc need his protection, maybe he believes that Ukraine's leaders are puppets of an American government determined to overthrow him and/or undermine Russia, maybe he thought the Ukrainian army was getting stronger and so he had to act now, and probably some part of most of the above (maybe not the meth one) and several others. The common denominator in all of these theories (maybe not the meth one) is that it is the combination of these beliefs of Putin, which are currently unknowable, with the Ukrainian move westwards, that has meant that the war is happening. 

Samo Burja has referred to Russia under Putin as a live player; a country able to do things it has not done before. This is debatable given Russian history (he defends his argument on the basis that post-Soviet Russia is a new country). What is unarguable is that Ukraine is a live player, and, given the situation outlined above, would be likely to remain one even if Zelenskyy was no longer President (as long as he was replaced by another leader chosen by Ukrainians). It is doing things it has never done before. These Ukrainian actions have led to a situation where a mass-murdering scumbag has decided to declare war, for reasons that are currently unknowable. But they also offer the hope that Ukraine can be a free, prosperous, democratic state. Ukraine is not a pawn of Russia, the US, or anyone else. The most important decisions that led to this war were made by millions of Ukrainians, and one evil Russian. 

Russia believes that independent Ukraine has become a tool with which to attack and undermine Russia. Russians say that since the cold war, America has reduced many countries to chaos - Libya, Syria, and Iraq are frequently cited examples - the main precedent here must be Yugoslavia. For Russia, "losing Ukraine" is very similar to Serbia losing Kosovo. It's a kind of motherland and to have anti-Russian ideology there is unacceptable - this is the real meaning of "denazifying" Ukraine - in Russia, Nazis are remembered primarily as enemies of Russians. 

Petr Pascenko commented that "half of the Russian defense industry has ended up in a hostile country". So there you see the other war aim - disarming Ukraine. To say Ukraine is militarily irrelevant because this is the era of nuclear weapons, is to overlook a lot of things. There is a continuum of escalation from political subversion, to guerrilla forces, to conventional warfare, to nuclear war, and control of territory still matters for all of them, even for nuclear war: territory can house missiles, missile defense systems, electronic monitoring stations, and special forces. 

Even with a Russian victory, Ukraine's military-technical potential would not soon be reintegrated into Russia's system, so I believe the immediate goal is to just neutralize that potential, first by force, and then politically. 

The timing of the war, I attribute to the manner of the American exit from Afghanistan. Russia's analysts and strategists may have decided that America looked weak, and that there was a chance to kick them out of Ukraine entirely, rather than just keep Ukraine preoccupied with the civil war. So first there was the ultimatum of December, demanding a treaty to restrict NATO and keep Ukraine neutral; and when no treaty was agreed, then came the actual invasion. 

For me, the biggest riddle is still, what have American intentions actually been, through all the years; how should one conceive of them. (There is also the question of European intentions, but I'll skip that for now.) There's little doubt that American "grand strategy" includes among its aims, preventing any great power in the eastern hemisphere, from becoming dominant there. Another common element of American geopolitical thinking since the end of the cold war, is the idea that spheres of influence should not be allowed. Each nation, no matter how big, does not get to influence the sovereign choices of its neighbors. Finally, there's that end-of-history idea that liberal democracy is the final and most virtuous political system, and that it should become universal. American policy towards Ukraine and Russia can be motivated by all of these. 

Trying to map hypothesis space of the Real Reason (tm):

1: Basic western narrative. Putin feels backed into a corner, like he is slowly but surely loosing influence to the West. He has the Mafioso-nature, and thought that taking back Ukraine would be easy, popular at home, a real show of force to the rest of the world short term, and could even be an economic win long term after consolidating the new territory and work force, plus it would cement his legacy as a Great Russian Tzar. But he has lost some of his touch and miscalculated, and is now a dangerously flailing wounded animal. Maybe also influenced by the newly found gas fields i Ukraine. 
Most of my probability mass is spread around here, though not really sharply concentrated anywhere within this branch.

2: Basic Kremlin narrative. Russia feels backed into a corner, like they are slowly but surely loosing influence to the West. The anti Russian Rusophobic sentiment in Ukraine is real, and the Azov Battalion is only the tip of the iceberg, and Putin wants to save his fellow Russians and Little Russians from US/Nazi oppression. Zylenskyy may or may not be a literal nazi and/or Jewish, but he definitely is a literal actor, and is playing the media and the west like a grand piano, according to the whim of the US, while the US is making biological and/or chemical weapons (the story varies) in Ukrainian labs to kill all Russians. Also they never even invaded Ukraine in the first place. 
This story isn't even trying to make sense.  

3: Putin might have some brilliant ace up his sleeve that will make it all come into a new light once it is revealed. I'd be very surprised at this point. It would have to be a very brilliant ace indeed. The only thing that even comes to mind is that this is a ruse to fool the west into thinking that the Russian military is weaker than it really is, then ???, then profit. 
I don't see it.

4: This invasion might itself be a reaction to something hidden, like a forced move due to invisible-to-us forces. Either in the Kremlin, on the streets of Russia, other world leaders, or China. If this comes from outside of Putins control, that could explain why the invasion seems so rushed and ill-prepared. But this also doesn't really seem very likely, when the very basic narrative seems to explain what we see equally well, but has fewer moving parts. Also, he has been nourishing this conflict for years, built his troop presence for months, and has been writing and opining about Ukraine for long time, so it doesn't look like a forced move. Hard to tell. If this was the case, then I wouldn't really expect anyone in the west to be able to see it until after the fact.

5: There is some huge benefit that he's after, but that we can't see. Maybe there are some complex ethnic stuff that the west hasn't picked up on (there surely are ethnic tensions, but the ones I've heard about seem inadequate to motivate all this). Maybe there is some complex strategic reason, having to do with the specific ranges of different launch systems and their positioning.... But I don't see it. Maybe there is some forgotten secret Soviet research facility hidden somewhere in Ukraine. Maybe the Lost Ark is in a catacomb under Kyiv. 
This line of reasoning is highly speculative at best, but would of course be an enormous breakthrough and of extreme strategic importance if it was true and could be found out. I don't think it is true. 

6: Truly alien motives. For example, Putin has himself stated that the Cold War era was better and safer for the world, and that this dangerous era of "monopolar" power distribution is terrible. Maybe the entire point is to spark a new Cold War. 

6.5: Putin is literally going mad, after years of self-imposed isolation and KGB-trained paranoia, maybe with a flavor of dementia in old age.

7: ???

In the end I don't really feel very confused about this war. It took me a few days for the shock to wear off, but to me it frankly looks a lot clearer than most wars I've ever studied in detail. This is not to claim that I got it right, of course. Most of my probability mass is within the scope of the mainstream western narrative. I would like to note however, that IFF he would indeed have taken Ukraine in a short, heroic war were he was welcomed by a sizable part of the population, many of these benefits would have likely materialized, regardless of our misgivings. Crimea worked out great for him. I don't think he miscalculated by all that much, aside from the true shape of his fighting forces, and the degree of support in the Ukrainian population (huge though those are). Note that I am in no way saying that the entire mainstream narrative is accurate or anything sweeping like that. Just that I haven't yet found any compelling evidence far outside of it. If you feel like you have some, I'd be most interested. 

No one really sees into Kremlin inner circle decision making but there are several plausible hypotheses:

1. Snack that went wrong
As noted above, previous Putin wars (Chechnya, Georgia, Crimea) were in general short, victorious and boosted Putin's popularity, and strengthened his regime. At least so far.

2. No democracy in our backyard
A possible prospect of prosperous democratic Western-oriented Ukraine is probably the biggest threat to the long-term stability of Putin's autocracy.

3. Time is not on our side (my favorite)
Contrary to popular belief and the Russian propaganda narratives, sanctions do hurt. The ability of RF armed forces modernization as well as general Russians prospects for sustainable growth is effectively blocked. Hi-tech imports are prohibited and half of the Russian defense industry has ended up in a hostile country. The best time to do something is now, better than, say, ten years from now. Also, the west is still busy with covid, and oil and gas prices are rising. Nothing to wait for.

4. Place in history
Russian history books in general praise the leaders who succeed in the task of significantly expanding the territory of the Russian state, whatever the cost. Ukraine definitely counts and Mr. Putin's time is running out.

5. Victim of his own lies
The problem with politicians is that over time they come to believe their own propaganda. So long you say Ukraine is no country and Ukrainians are no nation you lost track of what the truth is.

Richard Hanania's Public Choice Theory and the Illusion of Grand Strategy is worth reading on this general topic, although it's mostly about the Iraq war.

He doesn't use these words (that I recall, and I'm only partway through), but the behavior of states is less like rationality and more like autism.  What I mean is that states act on internal motivations that are only very weakly coupled to the objective strategic reality.  

Putin probably didn't have access to reliable information about the capabilities of his military vs. Ukraine's military.  How could he?  What General would dare tell the Tsar that the Russian army sucks?  Who would dare tell the General?  I'm sure the soldiers and junior officers knew they had problems, but probably had little idea how their capabilities compared to the Ukrainians' capabilities.

On the other hand, Putin probably knows as much as anyone about the highest ranks of Russian politics.  He sees those people all day, and it's almost inevitable that they constitute the community that matters to him. 

If you haven't read it yet. 

https://www.lesswrong.com/posts/mtBezwiwnELSjCxgq/ukraine-3-decision-theory-madman-theory-and-the-mafioso

One interesting aspect here is that Russia's stated reasons aren't just confined to NATO. Part of the stated reason is that Ukraine didn't follow through on their Misnc II agreements. 

All of the previous wars have been easier to understand.

Wars are probably easier to understand in hindsight. During a war, there are incentives to lie about many things.

NATO is only a defensive organization.

It is now, and hopefully it stays like that; but it makes sense to worry about what else could happen.

I can't see how Russia's regime has anything to win with this on the long run. They might suceed at installing a puppet regime in Ukraine - but why is that so terribly important to them, and even more importantly, at what cost? Maybe they are just irrational? Maybe they were just wrong?

The war is not over yet, so it is too soon to talk about who was wrong.

There is always some uncertainty about how people will react. Perhaps in many parallel universes, Ukraine already has the puppet regime, and what we observe here is a rare outcome.

Cost? What ultimately matters is the impact on those who make the decisions, and it doesn't seem like Putin's position would be significantly threatened just because a few thousand people die. Sanctions? Well, they probably did not happen (or at least were much smaller) in those universes where the war actually was quick.

But Russia invading Ukraine, when the most that is feasible is a regime change...??

And in long term, unification of Russia, Ukraine, and Belarus. If we can trust Putin's own words, of course.

I am struggling with the same question, my current hypothesis:

1. it’s “European Gas Wars” - new method of gas (mining??) from drilling in shell rocks see https://youtu.be/If61baWF4GE puts Ukrain into top position as gas exporter in Europe and nullifies Russian position as gas exporter. It’s quite plausable and verifiable - Shell signed a multi-billion contract with Ukranian president in 2013 to build infrastructure.
2. Russia does somebodies else bidding - Chineese to push US out of world dominance, i.e. this hypothesis assumes there are few more moves after Ukraine invasion and escalation of conflict through the world From Russian perspective this invasion makes no sense at all - i.e. if Putin wanted to defend Donbass, 8 years ago was a right time, if NATO is a defence force, and Ukraine can be part of NATO, why Russia can’t be part of NATO (against China for example??? IMHO NATO is a construct designed to be against someone). I could come up with few “retaliation” strategies from Russian perspective which doesn’t involve invasion: i.e build cosmodrom in Cuba (with full radio location equipment) and I think Putin advisors can come up with better once.
3. It’s Putin’s “Bay of Pigs”, but it lack a leader to re-instate back as president of Ukraine.

The so-called danger that Moscow is very hard to defend from Europe because of the vast plains, therefore needing buffer states, doesn’t make any sense when nukes are in the equation.

By this logic wouldn't most of the military of all countries with nukes be unnecessary? As I understand it, the way you do it with nukes is you put as many steps as you can before you are forced to use them. So allowing for indirect confrontation in puppet-Ukraine that even in case of defeat may result in long-term recognition of Crimea as Russian territory seems positive. Or at least it may seem so to people in charge with 19th century-like thought patterns. You also may leverage puppet-government for gas exporting infrastructure or something? So it leaves the costs and that part really seems like miscalculation.

Russia wants Ukraine to stop doing ethnic cleansing in Donbas? I'll propose that the world makes perfect sense and everything fits together if you believe the Russian narrative, whilst nothing makes sense and nothing fits together if you believe the western narrative.

Going forward from there, the problem is, so, Ukraine shot a plane down, and the west blames Russia. Do the Russians swallow their pride and put up with this, or do they escalate? And of course they escalate. So, the Russians "suddenly and without provocation" seize Crimea and Donbas in a wildly popular referendum. Does the west back down, swallow their pride and put up with this? No, of course not, they escalate. So does Russia swallow their pride, put up with constant taunts, terrorism and (almost certainly empty) threats? No, of course not, they escalate. So does Ukraine surrender before overwhelming force? Nope, that also requires they swallow their pride.

Now, I'm getting into more speculative territory, but I expect that Russia simply doesn't want to kill Ukrainians. They want to Win. Winning is an end to itself at this point, with no other purpose. Because they're sick of being nettled by the evil westerners and want to show them what for. I am fully convinced the Russian war aim is for Zelensky to say "You win." and that this entire war would be over tomorrow if he did so.

So, the Russians take up lines, and they sit and wait. Militarily, Ukraine should shortly (over the next few months) run out of supplies and become incapable of continuing the war. The typical Ukrainian soldier is not actually willing to die for his government, but he doesn't have to, because Russia isn't trying to kill him, just wait him out. However, Zelensky's gambit is that he can use his utter dominance in the western press to spin the narrative to his advantage. And in fact, the number of people calling for intervention is increasing daily with each new story of Ukraine's heroic resistance and resolve, as they sit around and do nothing. Of course, Russia, and in particular, the Russian government absolutely cannot afford to lose at this juncture. They would be overthrown and executed. So they won't lose.

Which brings us to global thermonuclear warfare.

Or we could choose the alternative, and Lose.

So long story short, it's a war over national pride. The west insulted Russia one too many times, and they threw a hissy fit, and now the west is split between the side that thinks we should discipline the whiny toddler and the side saying "Umm, they have nukes? This is bad? Can we, not do that?"