Is my reason for apprehension valid?

Hot war with China would take at least a year to build up. Most likely scenario is over a Taiwanese invasion, in which case US, Australia, Philippines, Japan, S. Korea, and NATO allies would be involved.  The Ukraine invasion was telegraphed for 4-6 months, but it was obvious as the Russian Federation had committed 90% of their entire army to Western Russia and Belarus. People didn’t want to believe it because they had buried their head in the sand.

China would not want to start a first strike nuclear war in the absence of clearly telegraphing the development of other forces (conscription, naval exercises, preparing transports, etc.). Their nuclear capabilities are much weaker than the US. That’s Russia’s job, because they have a lot more nukes. 
Because of consumption culture in the West, China’s best friend is the US economy. Why blow up your customers? China’s economy is much more reliant on the US than vice versa. Look at imports-exports by country and partner. 
In a Chinese first-strike military scenario, the US retaliation would likely be way worse, and there would be hundreds of millions of deaths from destroying the Three Gorges Dam alone. There’s no similarly vital target in the US. 
The threat is small, not in China’s interest, and would be telegraphed for several months.