Because Taiwan is the casus belli for the war. The US cannot afford losing the “center of gravity” status in the world economy, and China was going to take that

Because Taiwan is the casus belli for the war. The US cannot afford losing the “center of gravity” status in the world economy, and China was going to take that away within a decade. By some metrics it’s already gone. It’s clear that the economic war is not going to work, so the usual solution for such a thing is to create a persistent source of instability right next to China, armed to the teeth and ready to die. Same as the US could not afford to lose control in Europe, so it decoupled Russia from Germany by funding a war on Russia’s border and blowing up Germany’s energy supplies. Or how the US was worried about the Arab world unifying and constraining its choices in the region, so it started half a dozen wars there. Or how the US was worried about South America and started wars there as well.