I disagree that the war is "sustainable for Russia for years to come" -- you are right that Ukraine needs a lot of support from other countries however also Russia is dependent on support from China, North Korea to keep things running. If in particular if China stopped all support Russia would soon run into issues. So both parties are dependent on other countries to keep the war going at least at the current level.
This isn't really the same. China isn't supplying aid to Russia for free. Russia is buying what they need. And they're buying it from many countries. Ukraine can't buy what it needs, they can't even pay their government salaries without foreign aid. This is one of the factors that makes the war sustainable for Russia and unsustainable for Ukraine. If Russia depended on political decisions to allocate funds to support their war efforts, their position would be much more precarious. Instead China (India, Iran, Brazil, Indonesia, Nigeria, etc.) has to simply not join sanctions against Russia.
This is key to understanding Ukraine's problem. The total volume of aid to Ukraine has been massive but the aid levels have been inconsistent, they've gone down over time, and they've been largely "take what we have" not "here's what you need". Let me give you a prime example. Ukraine badly needs good AAA to deal with Russian drone attacks. The Gepards they got from Germany are a good example of an older system that's nonetheless doing valuable work. However they only got ~100 or so of them. They need more like 1-2
thousand such systems to cover all major urban areas. The logical solution for aid to Ukraine is to produce modern versions of the Gepard and deploy them to Ukraine. Enter the German Skynex, of which Ukraine got.... 8. Eight. Let that sink in. 8 in 3+ years of Russian long-range strikes. The Brits jumped in to help recently and handed over the Terrahawk Paladin. 4 of them. Is anybody working on a plan to ramp up AAA for Ukraine in bulk? We're about to be in the fifth year of this war (in a couple of months).
Russia doesn't have this problem. Russia has other problems, sure, but not this one. If Russia needs more AAA, they can produce it themselves, with inputs sourced from China, or India, or anyone else willing to sell to them. And despite all the lies from politicians, Russia is not isolated internationally. Much of the world is simply willing to keep trading with Russia, as long as they're not actively involved in supplying the military directly. Some are willing to trade with Russia even when they are actively involved in supplying the Russian military. Prime example, Streit Group delivering armored vehicles with American components to the Russian National Guard. Or Egypt getting caught selling munitions to Russia. These players aren't making the political decision to allocate resources to support Russia's war effort. They're simply profiting from the war. There's a huge difference, and you're attempting to plaster over it with equivocations.
All the evidence points to Russia invading Ukraine not because of a hypothetical "NATO threat" (irrespective of that perceived threat being is real or not) but because they wanted to expand their empire. Ukraine was not about to enter NATO, and Russia knows full well that just the threat of invasion would have been enough to keep Ukraine out of NATO, indefinitely. However, Russia wanted much more than that, they wanted their empire back. Putin found it difficult to build an empire without invading Ukraine. So from his perspective it was logical to invade. Most people in Europe will not accept this, and therefore we should and must support Ukraine until Russia accepts that they must stop this madness. And Ukraine should of course be accepted into NATO, if they want to of course.
Russia can of course believe and say whatever they want. What they cannot do, is invade other countries in Europe, whatever reason they have invented for doing so, and I believe there have been many (NATO, de-Nazification, de-satanisation, de-jewification, etc.).
No that is not where all evidence points. Mostly the evidence points to Russian leadership realizing the Minsk Accords were a dead end where Ukraine would simply refuse to execute their part of the deal under varying excuses, while continuing to drag out the conflict, and keep Russia tied down. They went into Ukraine in 2022 with an idea of regime change and a forced resolution to the Donbas conflict from '14. Only when that failed did they shift their goals to include territorial expansion, presumably as a way of punishing Ukraine for refusing the Istanbul Accords, and instead trying to win the war militarily.
Yes, I am genuinely surprised.
I understand resentment over sanctions, companies leaving the country, frozen assets, barred athletes, and the way Russians are supposedly portrayed in Western media. What I struggle to understand is how these grievances translate into a widespread willingness to have one’s sons and brothers sent to die in a foreign land (which is not even a Western country). What does that solve?
It's not seen as a foreign land. It's seen a sort-of Russia (large parts of it anyway) that got independent in '91. That's a big part of the views on this. And again, remember it's not your sons and brother getting sent. It's largely voluntary enlistments that are generously compensated. If one's son or brother opts for a 6 months enlistment and comes back with enough cash to buy a home, wearing medals, and looking pretty in their uniform, you may have had misgivings about it but you're not going to be against the war. In poorer parts of Russia, the influx of war cash has been a real boon. And in richer parts of Russia you don't have to go to war, you can just keep working your job, living your life, and pretending there is no war.
At this point it is quite irrelevant I suppose, Putin can't just say "major victory: after four years and a million casualties we conquered 10% of Ukraine and not even the entirety of Donbass...
He can say it, the question is whether people would believe it. And let's be clear, it's more like 20% of Ukraine now. This is also key to the ongoing peace negotiations - all of the Donbas. Russia is requiring Ukraine leave the rest of Donetsk region as part of any ceasefire deal. Clearly Putin isn't willing to declare victory without taking all of the Donbas. And he's on track to do so by the end of next year, give or take.