I understand the whole idea of playing Chicken is knowing when to flinch, but I think we should try to cool things down a bit.
People who lived it or know their history, know how upset the United States was when the Soviets put missiles in Cuba, 90 miles from Florida, and was going to station troops there. Ukraine is directly on the Russian border in an area that has throughout the history of Russia been a weak point and Russia had always made it a point to have "Buffer states" along their western Borders. Why? Because of Geography, the Western Bprders of Russia are mostly open plains and flat land on the Great European Plain. Napoleon wasn't defeated until he reached the far interiors of Russia and dealt with the harsh winter conditions, same is shown by the German invasion in 1941 and their success from June of '41 until the winter of '41-'42.
It may be unpopular but there are some geopolitical realities in regards to what are absolutes and what may be able to be compromised through negotiations.
Absolutes:
1. Russia is never going to surrender Crimea to Ukraine in any peace agreement. Why? Again, Geography. The port of Sevastopol is the only Naturally protected Port the Russians have in the Black Sea and has long been the HQ of their Black Sea Fleet for Centuries. Crimea was not considered Ukrainian until Kruschev put it under the Ukrainian Soviet Socialist Republic as a way to apologize for how Stalin had treated the Ukrainians as part of his Destalinization campaign.
2. Russia is never going to accept Ukraine being part of NATO same as we would never accept Cuba having Russian missiles. Ukraine has to be left as it was intended by the Protocols established when Ukraine gained its independence and remain militarily neutral between The West and Russia.