I agree an extent, but that's also why you have established nuclear powers to begin with -- i.e.: that nuclear powers recognize and respect each others red lines and that they respect there are certain legitimate things that they can have the right to put the nuclear option on the table for.
The nuclear factor in a Taiwan contingency is essentially to raise the stakes to the US that the nuclear option very much would be on the table in some forms if the US chose to intervene, to introduce that level of strategic and potentially world ending doubt -- not necessarily a threat that the button would immediately be pushed the moment the US intervened.
Essentially it would be challenging the US to the extent to which they are committed to Taiwan, while also seeking to establish China's degree of resolve as well.
I think Mao had the right idea about Nukes when comes to war. They are paper tigers. Completely useless. Nukes are only good for one thing, to deter others from annihilating you. They are essentially suicide bomb attack on your enemy.
They can raise the cost perception of starting wars between major powers. But they are not really good for actual war.
War is about gaining land and destroying enemies at minimum cost to yourself. What good is a war if you destroy yourself in the process?
In fact I would argue that even in the face of total defeat a country will not use nuclear weapons. Why? Because using nukes means not just defeat, but complete annihilation when the enemy also attacks you. Sure you take out the enemy too, but what's the point of taking out the enemy if you die as well. Is the cost of defeat higher than complete annihilation? I would say, No.
A rational human being and a country that is composed of rational human beings will never choose to do a suicide attack compared to surrender. Because surrender gives you a hope that the enemy will be merciful and might spare you to live another day.
When a soldier sees a gun pointed at them, they don't choose to commit suicide to take out the enemy with them, they choose to surrender with the hope of surviving the next day.
So, there is no nuclear option for China or any other country when it comes to preventing others from attacking you. You can use nuclear weapons as tactical nukes to gain advantage during war, but they cannot prevent war altogether from a determined enemy. If US decides to invade China, would China start nuking US cities? Of course not. Why commit suicide when you can defeat a US invasion with an army anyway?
Even if China was losing to US and getting completely taken over by US, why would they commit suicide by attacking US cities when they can surrender and become like Germany or Japan. Sure, its humiliating but its better than complete death.
Same thing goes for US if there is ever is a scenario where it is facing complete defeat by China in a war. There is no way US will commit suicide just cause they are losing to China.
There is no alternative to conventional military power. They will always be useful to win wars and gaining a political outcome.
What prevents war in the modern day and age is not nukes but economics. In the past, nations gained power and resources by gaining more land, since all money was gained from agriculture. But in the modern era, trade and technology has changed the dynamic of how nations become rich. Now you can buy resources with money. How powerful and rich you are is determined by your industry, education level, technology and so on. There is no extra advantage at gaining more land.
US can say all they want how they will give up everything to save Taiwan. But if China becomes 3 times bigger than US in GDP which is very likely by 2050, and also starts to field military budgets 2 times that of US, also very likely by 2050-60, then what good is saving Taiwan? US will be completely outgunned and overwhelmed by Chinese military power that will threatening them all across the globe. The raw numbers of Chinese planes and ships will make any kind of defense useless near Chinese coast. US will have to think how it can save Latin America from Chinese dominance, let alone Taiwan.
China will gain Taiwan without a fight once they get as rich as Japan which will likely happen by 2050. US will by then give up on Taiwan just cause they will forced to focus on detering China in their own shores.
