[Detrytus]

But those are small, isolated attacks. Front line is still deep in the Ukrainian territory. If Ukrainian counter-offensive manged to move it deep enough withing Russian borders, Russia would nuke them.

And as for consequences I do not think the West would do anything about that. US won't go on full scale nuclear war with Russia over some insignificant country at the end of the world, that isn't even a NATO member. So the worst outcome of nuking Ukraine for Russia is to get even more economic sanctions, that's all.

[racional]

And as for consequences I do not think the West would do anything about that.

The worst outcome of nuking Ukraine for Russia is to get even more economic sanctions, that's all.

The response won't be nuclear, per its stated posture on this. But it's hard to imagine the United States would do basically nothing of substance in response, and it hasn't ruled out a violent conventional response. And at least back in 2022, Biden took care to put this messaging out indicating there would be a "consequential" response, per his interview with Scott Pelley:

  "And I wonder, Mr. President, what you would say to him if he is considering using chemical or tactical nuclear weapons?"

  "Don't. Don't. Don't. You will change the face of war unlike anything since World War II," Mr. Biden said.

  When Pelley asked what the consequences would be if Putin crossed that line, the president wouldn't say.

  "You think I would tell you if I knew exactly what it would be? Of course, I'm not gonna tell you. It'll be consequential," Mr. Biden said. "They'll become more of a pariah in the world than they ever have been. And depending on the extent of what they do will determine what response would occur."

https://www.cbsnews.com/news/president-joe-biden-vladimir-pu...

US won't go on full scale nuclear war with Russia over some insignificant country at the end of the world

First, while it isn't a NATO partner or of similar status, Ukraine is absolutely not "insignificant" to the at least the current administration in the U.S., and the whole Atlanticist crowd. It would not have stuck its neck out (and expended its political capital) as far as it has on Ukraine's behalf thus far, if that were the case.

And while it won't go nuclear over Ukraine -- it is definitely concerned about its strategic posture and global stability, and the detrimental consequences of giving Russia perceived "pass" to use nukes in any offensive context. And would basically have to make some kind of genuinely serious response. Which some people close to the administration have quietly hinted could be a conventional military response.

[Detrytus]

I'm not sure how that "conventional violent response" would work.

Russian military doctrine includes nuclear first strike when there's an "existential threat" to Russia, even if that threat is from conventional military attack. If Russia can use nukes against Ukrainian army entering the Russian territory, then for sure it would use them against NATO troops doing the same.

Also, in such a dire situation, Putin and other Russian leaders are crazy enough to use not just tactical nukes but to start full scale nuclear war without any hope of winning, just to "go with a bang".

[racional]

I'm not sure how that "conventional violent response" would work.

One can imagine scenarios of varying effectiveness, but this a separate matter. The point is -- the Biden administration has made it clear to the Russians that there would be a significant response, with strong hints that it would be military in nature and not limited to extra sanctions.

If Russia can use nukes against Ukrainian army entering the Russian territory, then for sure it would use them against NATO troops doing the same.

The response doesn't need to involve NATO troops in Ukraine.

Meanwhile it'd be kind of hard to use nukes against stealth bombers, cruise missiles, drones and SF operations.