[Goose]

Of course, we have nuclear weapons, but under what circumstances will we use them?

I wonder how much that doctrine has changed over the past 30 years?

Good question. The US has always utilized "strategic ambiguity" to cause other nations to be unsure where the boundary was and therefore be cautious not to cross it. Similarly we have never signed on to any "No first use" pledge because 1) we have already done it once and 2) no nation will honor such a pledge if they believe first use is in their strategic interest. The President can order their use using whatever advisors (if any) he wishes to consult. POTUS has absolute authority. While there is plenty of scholarly analysis on the subject it comes down to what the President  thinks is prudent. This is one reason it is imperative the President be able to evaluate the situation rationally, dispassionately and logically. The POTUS can't be driven by emotion (like anger or fear). The POTUS also has to understand the consequences of acting or not acting (in so far as it is possible) by taking into account all the available facts and precedents. As far as I know no POTUS has ever come close to actually giving the "go" authorization. Let's hope it can stay that way.

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Unfortunately, Ukraine isn't resourced to conduct such a breakthrough. In their wildest dreams they aren't going to threaten to occupy Russia. The best they can hope for is to drive Russia out of Ukraine and then obtain a political solution. If Russia decides to keep fighting there is nothing Ukraine can do about it. This is the conundrum of this war. No matter how well Ukraine fights, this war ends only when Russia "wins", cannot continue because of economic collapse, or will not continue because of political unrest and/or an outbreak of common sense.

I wouldn't count on that last one...

I definitely am not. Such outbreaks are exceedingly rare in Russia, and when they happened in the past they paradoxically often make things worse, not better.

[Goose]

Of course, we have nuclear weapons, but under what circumstances will we use them?

I wonder how much that doctrine has changed over the past 30 years?

Good question. The US has always utilized "strategic ambiguity" to cause other nations to be unsure where the boundary was and therefore be cautious not to cross it. Similarly we have never signed on to any "No first use" pledge because 1) we have already done it once and 2) no nation will honor such a pledge if they believe first use is in their strategic interest. The President can order their use using whatever advisors (if any) he wishes to consult. POTUS has absolute authority. While there is plenty of scholarly analysis on the subject it comes down to what the President  thinks is prudent. This is one reason it is imperative the President be able to evaluate the situation rationally, dispassionately and logically. The POTUS can't be driven by emotion (like anger or fear). The POTUS also has to understand the consequences of acting or not acting (in so far as it is possible) by taking into account all the available facts and precedents. As far as I know no POTUS has ever come close to actually giving the "go" authorization. Let's hope it can stay that way.

---

Unfortunately, Ukraine isn't resourced to conduct such a breakthrough. In their wildest dreams they aren't going to threaten to occupy Russia. The best they can hope for is to drive Russia out of Ukraine and then obtain a political solution. If Russia decides to keep fighting there is nothing Ukraine can do about it. This is the conundrum of this war. No matter how well Ukraine fights, this war ends only when Russia "wins", cannot continue because of economic collapse, or will not continue because of political unrest and/or an outbreak of common sense.

I wouldn't count on that last one...

I definitely am not. Such outbreaks are exceedingly rare in Russia, and when they happened in the past they paradoxically often make things worse, not better.