As for the argument that popular opinion will turn against the west: it already has [2] and I think we should not talk about sanctions any longer, but of separate blocks with minimal exchange and interaction. I understand that going back to an iron curtain of some sort may be shocking for some, but at least that will severely limit the risk of miscalculation and nuclear war. Putin is a dictator and we have to act.
[1] Says a former Russian diplomat: "They also thought the EU was weak because of how toothless their sanctions were in 2014" https://twitter.com/andreivkozyrev/status/150061067692600525... [2] https://twitter.com/ABCNewsLive/status/1499449302728462342