In addition, usage of tactical nuclear weapons comes up again and again from Russian sources, driven by the situation in the Ukraine war.
https://www.axios.com/2026/04/03/military-officials-ousted-r...
https://www.militarytimes.com/news/pentagon-congress/2024/10...
https://www.japantimes.co.jp/news/2026/07/11/asia-pacific/ch...
What if they did it? They would be a paria politically, but countries would still buy their oil/gas because they need it and it's cheap, nobody would start nuking Russia over Ukraine [1], and using tactical nukes against nations that don't have them would become much more acceptable.
It is kind of telling that China has to be the ones reigning them in, which is a good sign that they are replacing the US as the world's superpower, which also comes with maintaining some stability in important markets, erm, countries.
Aside from that our best hope is that the functional Russian arsenal is much smaller than Russian claims due to the lack of maintenance, corruption, etc.
[1] Trump would just have a phone call with Putin and then parrot whatever narrative the Kremlin has. For France and UK, nukes are purely for self-protection, so they would only trigger a counter-attack if Russian nukes appear to be coming towards them (so it's probably better for Russia to avoid The Netherlands and Belgium too).
The moment you use them, you lose their value as a deterrance anymore.
If they used nukes in Ukraine, the strategic deterrence against other nations with nukes would still be in place.
They didn't use them against Ukraine because of many other reasons, e.g. because they would have taken Kiev in days, it didn't make sense to make land that you want to conquer radioactive, and the political fallout would be too big.
I think now they won't do it because China is too important to them and China made it clear that using tactical nukes is out of the question.
No it wouldn't be a deterrance anymore again other nations, it will be an actual threat. If they actually do show they are willing to use them in any capacity, esp over Ukraine which is agression they started, other countries cannot just ignore it or bow down to Russia. It also not a deterrance to nuclear powers in the first place and in the second, it becomes an existential threat again.
As for why they didn't use it in Ukraine is primary because they have never done so. The political fallout will be suicide, there is no other option.
I don't see how China fits in with the tactical nukes thing. Your position of "Russia could have nuked, they just didn't want nuclear fallout, political fallout and China being mean" instead of "they didn't nuke because it will be unprecedented and consequeunces will be dire bodering on absolute destruction" seems weak to me.