Don´t you think that the costs of this war will be quite high for Russia compared to the gains?
No, @stayoutoftherz. Russia has a security concerns that has put it in the position to take – in chess language – forced moves. As a country, Russia is self-sufficient, they have enough food, energy and military power until the end of the World. The only thing they don't have is an agreement on mutual security with NATO. Have you heard announcement of Zelensky that he will re-arm Ukraine with nuclear weapons?
No, I was not aware. It is of course unacceptable to deploy nuclear weapons in Ukraine.
USA would also not accept that Mexico buys and deposits some nuclear weapons at it´s border to USA.
!hivebits