[sudosysgen]

77 billion is the price to do it right over 5 years. If you don't care about quality and are willing to spend more you can do it faster. We have historical examples of this.

The pipeline capacity alone from Russia to China is 1.6mbd. Of that, 600 000bd are used, so there is 1mbd of spare capacity just in that pipeline.

It doesn't really matter if the US can or can't back down. It will be disastrous politically and economically to the US and its allies to a level that can scarcely be imagined. Even then, US naval forces have a serious chance of defeat. China is not a small country you can roll over. They have a very well thought out, multilayered, exceedingly technologically sophisticated A2/AD umbrella that means that millions of square kilometers will be in practice off limits to the US. Beyond those zones, China enjoys extremely prompt hypersonic strike capability that has no real counter, which means that in a hot war any US vessel that gets it's rough location leaked running a blockade or running through a strait risks getting sunk straight up.

It's not a war that the US can win. What are the objectives? Take back Taiwan? Literally impossible. Regime change in China? Forget about it. About the only thing that can be done is to hurt the Chinese economy roughly as much as the US economy, enrage the entire rest of the world and destroy any semblance of goodwill the US has, and trigger a recession followed by a restructuring of the US economy that reduces the place of the US in the value chain.

It's simply a stupid move that has no upside. It doesn't matter how the public acts immediately, eventually the US will have to give up.