It seems to me that the world would harden against Russia if it used Nukes. I cannot imagine India or China saying. Hey they enemy of my enemy is my friend, so why not let a few more nukes go.

If the west could hold its nerve and NOT nuke back, it seems that all flights entering or leaving Russia would stop. All oil purchases stop.

Their economy WOULD crater, and folks inside Russia would be looking at a future quite similar to North Korea. I don't think anyone in Russia wants to live as they do in NK. So I think Putin would loose power.

Now if the west hit back with nukes, who knows if we would have a planet to live on. I think there would be a decent chance of a coup happening right when Putin gave such an order.

I see no future where Russia is better off because it launched a Nuke... so I don't think it will do it.