Read: China Stages Last Minute Live Fire Drill In Show Of Support For Russia, page-24

Sorry I don't understand what you are saying is a fact?

Vietnam cost them more like 58,000 US lives so you're a fair bit off. I suggest you do some reading about the Vietnam War and what exactly held the US back (for good or bad) to gain a better understanding of the conflict. It was certainly not the most crushing defeat in human history as you have stated...