Except the paper signed was considered "outdated historical documents."

What didn't happen with HK was a change of law or legal precedent, what changed was who the military was and therefore the ultimate enforcer and interpreter of the law.

Likewise, when it comes to Taiwanese legality it doesn't really matter what the facts are, it's clear that the US is acting as the dominant military and enforcing its interpretation of the law, if China becomes dominant, so to will Chinese legal interpretations. HK is an excellent example of how paper means nothing and power means everything. Legal documents and doctrine are not power, power is power.

> HK is legally under PRC jurisdiction.

This is exactly the purpose of saying 1 country 2 systems, which is exactly the same thing as saying Taiwan is part of china. The PRC is claiming jurisdiction.

China has presented to the world a "frame" of the situation, which they can make very painful to disagree with. So the question is will the US fully accept the frame once pain is applied. We already half accept it due to China's hand resting on the pain knob.