As I have written here before, Russia probably has not adequately maintained its nukes and therefore the threat is hollow. A strategy for the We4st to pursue might be to recall how we ejected Iraq from Kuwait under GHW Bush. The key there was that we limited ourselves and did not march to Bagdad as many wise people said. The effort in Ukraine could be similar. The West could announce its objective to spell Russia but not to pursue its fleeing columns to Moscow. Putin might not like losing but this avoids a nuclear exchange and could be seen as even face saving.