War game simulation suggests that an attempted Chinese invasion of Taiwan would fail, leaving Taiwan in devastated condition though unconquered, while wrecking the Chinese military and causing substantial casualties for the US and Japan. These casualties would be large by the standard of 21st century US wars, but small compared with what the US experienced in the Vietnam War or the Korean War.

Taiwan would rebuild its infrastructure with help. Being devastated for a decade is not as bad as becoming brainwashed slaves forever.

Another article about the same war games reports on projected political effects of the war's damage, but I think it exaggerates that. If the US had defeated China and still possessed most of its armed forces, no other enemy would risk a conventional war.

I wonder how this would affect global heating and climate defense.

The article also suggests how Taiwan could build a more effective defense for much less money.

If China were not a totalitarian dictatorship, I think it would choose not to attack Taiwan, rather than suffer such a defeat. Surely some sort of compromise and peace would be better for everyone. Even Xi might choose peace, and I hope he does; but he may not care about the cost or the casualties to China as long as he wins.