NATO can. Just like Ukraine did. Mass forces to attack and bad things happen.
Ukraine failed to deter Russia. Actually they did quite opposite - they did provoke Russia. If NATO countries are too provocative (as Ukraine was) - Russia will beat them. May be, Russia will slap them gently, as it was with Ukraine to coerce them into acceptable peace, or, what is more likely - will beat them hard to death.
My point is that depending on which side of the border you are on, that is the country you are a citizen of.
Citizenship is one thing. Ethnicity - is a bit different. If, say, Arabs are attacking Jews in Israel, Jews in the USA are feeling themselves attacked either (and trying to help their brothers and sisters). Same way, if Arabs in Middle East are attacked - Arabs in the USA often feel themselves concerned. "We [Arabs, Jews, Russians, Americans] are under attack. We are fighting back." It's really old pattern. "Collective self-defense", one of the things that make us human beings.
My family came from Austria, and I am 100% American. There is a big difference between citizenship and country of origin. Countries of origin have no claims to another country because of the ethnicity of some citizens.
Russians (or Jews) in Ukraine (most of them) didn't came in Ukraine. They are not descendants of migrants. They live on their own land. Just some freaking politicians decided that this land is not their, anymore.
I have friends and relatives in Ukraine, including parts still controlled by Kievan regime. They don't like that regime, they don't want to be abused and discriminated. Right now they are waiting for liberation by the Russian Army (to change Kievan regime or to liberate and annex their land).
Most Russians want the war to end.
Most Russians want acceptable terms of peace. If Kievan regime continue discrimination of Russian-speakers - they won't see those terms as "acceptable". What is even more important, if the discrimination continues - people in Ukraine will rebel and people in Russian Federation will support them (NATO or not NATO).
And no, quite significant part of Russians (especially of numerous poor ones) want the war to continue, because it is profitable, and significant part of the most numerous Russian opposition party - Communistic Party, see a world war as a chance for the world's Revolution, and many of Russian rich people (they are minority, but influencial one) - see the local or even regional war as a way to obtain new assets.
Generally speaking - everybody love peace. But in practical terms - war is still good.
Old drunk politicians' opinions don't count. Putin is the leader, let him decide what is best for Russia.
A lot of people trust Putin. But Russians do decide what is best for them. If Putin try to sell them something obviously wrong (like continue of existence of Kievan Nazi regime and continue of discrimination of Russians in Ukraine) - ok, they won't buy it.
Ending the war, getting Crimea and Donbas and other areas are a victory to celebrate, plus no more dying.
It is not about territory. If Kiev continues discrimination of Russians - Russians won't see it as a "victory" no matter what tales medoa will tell them.
1. I have multiple sources of information, we can debate whose is more accurate
No, you haven't.
2. I voted for Trump, and Trump's point of view is dominant. Biden was a senile idiot.
As for me, both of them are senile idiots, but it doesn't really matter. American opinion about Ukraine is irrelevant because America is not ready to sacrifice even one million of Americans to prove that their PoV is relevant.
1. I guarantee a nuclear response to a nuclear attack.
And who are you? US nuclear posture doesn't "guarantee" it.
Mutually Assured Destruction (MAD) depends upon assured total destruction.
MAD is a myth. And even if you believe in it... Man, I'm pretty sure, that you are not going to commit murder(including murder of people who you suppose to defend)-suicide just for the ritual jesture.
2. In a Russian attack of a NATO country with tactical nukes I haven't used "game theory" or AI to see which outcome is optimum. But if a NATO country has nukes, I believe that they would use all of them if attacked.
Really? Even if they known that it will mean virtually total annihilation of them?
3. Say Russia attacks Poland, where US troops are. We would respond forcefully if those troops were nuked, that's a fact.
May be you'll try. Its "Deterrence type 3" - ability to fight and win a limited nuclear war. The problem is, that the USA have the only one type of tactical nukes - gravity bombs B61 and not too many of them, without actual capability to deliver significant part of them to targets. So, after a short Limited Nuclear war the USA will face the choice: 1) surrender 2) escalate.
If Russia attacked Sweden, I'm sure that at the very least, the EU countries would respond with nukes.
There is only one EU country with nukes. It is France. There arsenal is insignificant and it is not supposed to defend other countries, for its use means suicide for them (for Russians will fight them back). You know, like a bee who can sting, but only by price of its own death.
4. Why would Russia have one cartridge and the US five regarding nuclear war?
Because Russia has better nuclear arsenal (especially about its counter-force capability), Russia has better ABD and EMERCOM, Russia has larger national reserves of foods and goods, better capabilities to prevent chaos and anarchy and so on...
We both have thousands of nuclear warheads,
Doesn't matter how many nukes you have in peace time. What is matter - how many of them will survive Russian first strike.
Both countries would be radioactive wastelands.
Really? Like Nevada and Las Vegas? No. Air-burst don't cause fallouts at all. One thousand of Russian nuclear bursts on US silos will cause deadly levels of radiation in significant parts of Wyoming and Montana, but those levels will fall to normal in few days.
Ukraine is not Russia's sister.
It depends. Some Ukrainians are my cousins.
Ukraine is more like Russia's hateful ex-wife. There is no winning a nuclear war, and you don't want to have a nuclear war to test the outcome.
Of course we don't want to test the outcome of a nuclear war. But much lesser we want to test the outcome of NATO's forces deployment in Ukraine. We do prefer nuclear war.
5. Looks like peace talks are scheduled. I hope a ceasefire soon follows.
We don't need ceasefire. We need reliable and lasting peace. And no, Trump talks a lot, but there are very few things he can actually do.