Either two things are going to happen.
1) Russia keeps their word and retaliates hard against the West or….
2) Russia will continue fighting Ukraine and all the Western media will say Putin was bluffing and is a coward.
The smart thing to do is #2 overall, maybe retaliate against the Ukrainian government much harder.
The popular decision, at least for Putin and his reputation, is #1 which he will face a lot of political pressure to escalate. However, this is what the Western governments really want, they WANT war, they are the ones provoking the war! So it's not the smart decision to take the bait however, temporarily, humiliating.