Erik, the USA was unwilling to have Russian missiles in Cuba, and Russia made it clear it was unwilling to have NATO missiles in Ukraine after NATO declared in 2007 that they were moving towards eventual integration of Ukraine.

We miscalculated how much Russia did not want this.

We should have remembered how much we did not want Russian missiles in Cuba (a lot!)

All that said, I would agree that there is not a symmetry between the west and east when it comes to self criticism and willingness to engage in atrocities.