Honestly, Doing our best to stabilize Russia and the former eastern republics, playing honest.. ( trust.. verify .. and slowly dismantle Nato into an EU organization that does not include the US as primary command and control ) The USA would still be there .. possible as a non aligned member to counterweight the other big players, but allow cross building of ties, promote a new era of government for the east, not the oligarch mafia mess.. stabilize, promote arms reductions, finally wind down from WW II and the cold war.
snuff out the Balkan fire before it can get going.
the Russians have to give and so does the west.. plain and simple. No Yeltsin might help.. or less drinking
If the Russians believe the west are being serious and are not trying to be a threat and that everyone gets to be on the same boat and playing field, I think they would join cautiously, not all at once, but over the course of a decade come to realize that the future is in a united Europe