I'm just an armchair general, so take this for what it's worth. I view US vs China in the same way I view Japan vs US in WW2. At the start of the war, we're going to start with the maximum amount of resources. We have more "Kinetic" energy. But I personally think China has more "Potential" energy. Unless we win in the first volleys of the war, I think China could very reasonably extend the length of the war, and ultimately win.