So China's problem is they are not having babies and will run out of people to exploit so you believe they will start a war with the most powerful country in the world which would greatly reduce their own population by annihilation?
You believe that is their plan to world domination?
No. I don't believe they will go to war to reduce their population. What I do believe is that the world is going to be impacted in a major way by AI and robots and that China is the first to experience that because 3d printers have eliminated much of their manufacturing and export business. But Taiwan has become the most important prize because they manufacture the chips that AI runs on. Whoever has the most powerful AI will rule the world and Taiwan at the moment is the one manufacturing those chips.
That said AI and robots will take the jobs of many people, simple economics. A robot that costs $120,000 can be leases for $30,000 a year. It can work four shifts a week, and is far more reliable than any employee you could get at that price. Also there is no liability, no risk of lawsuit, theft, or viral videos to destroy your business. Meanwhile AI is even easier to roll out to the fortune 500 companies. They have predicted that it will take 100 million jobs, but that was not clear, were they talking just about the US or about the developed world? In other words are we talking about half the jobs or a third of the jobs?
They are already anticipating this issue and so are talking about UBI (universal basic income -- ie welfare). But if you believe that then you also must believe that North Korea is a worker's paradise. When people have their jobs taken they will become useless eaters and they will use the health care industry to expedite their transfer into the after life.
Instead the only future people will have in this brave new world will be to get a chip implanted into their brain and to become a cyborg controlled by the AI system. That is why if you take that chip you cannot be saved, it will control your brain, what you see, what you hear.
But returning to your question, the reason no one seems all that worried about going to nuclear war is that they don't really care if half the world's population dies since they know that will solve this problem they are going to have with AI and robots taking their jobs. Also they have built great underground bunkers to sit out the wars.
One thing they are planning on doing is wiping out the power with an EMP attack or a destruction of a number of sub stations. Either way the cities will wind up killing themselves with looting and rioting while the elites hide out in their bunkers just like the movie "The Purge".