I'm sorry but if you think that's the case you have a fundamental misunderstanding of international finance. The US does not require Chinese money for anything, nor do we require any further purchases of our debt by them. They do this as a form of currency manipulation to serve their own interests, not ours.
Furthermore, as treasury spreads clearly show the world views the US as a far safer financial bet than Russia. Our economic power is almost an order of magnitude larger than theirs, and they are vastly more dependent on the goodwill of the international community than we are. In short, if it came down to an economic fight Russia would collapse in short order.
Now we can move to the military aspect. I presume you meant 'impotent' as opposed to 'impudent', but to be clear we could make very short work of Russia's military if we chose to do so. They are poorly equipped, generally poorly trained outside of some decent infantry, they use mostly outdated equipment (their best equipment is exported, ironically), and they are generally designed for operations inside of Russia as opposed to a fight against an actually capable military power. It would be a slaughter.
I'm getting a pretty strong sense that you are allowing emotion to trump rational analysis. You might be able to make the argument that due to a disparity in interest that the west is not as willing to fight over Ukraine as Russia is, but do not confuse a lack of interest with a lack of capability.