[sudosysgen]

No, it really doesn't. Japan doesn't have the capacity to deploy enough air power to affect the invasion. If Japan made the strategic mistake of getting involved militarily before the US, the Chinese would use ballistic missiles to strike Japanese airbases and supply infrastructure and carry on.

I agree it would do no good to have a war between the US and China for anyone. I want Taiwan to stay independent and chose its own destiny. But the reality is that China has an overwhelming advantage in-theater over anyone and it's only getting worse.