Firstly, thank you for using the word "propitiate" - as a former English Major it is not often that I get sent to the dictionary to look up a word! :-)
Secondly, I suggest you read this article about CIA Director Bill Burns. When Burns was the US Ambassador to Moscow, he wrote a very long and strongly worded cable to then NSA Condoleeza Rice, saying that "Nyet means Nyet" and that Ukraine in NATO was the very brightest of red lines for Russia.
https://libertarianinstitute.org/dont-tread-on-anyone/nyet-nato/
https://wikileaks.org/plusd/cables/08MOSCOW265_a.html
Thirdly, I suggest you watch this video of John Mearsheimer, who predicted the war and gave the reasons in advance.